Revert the apt cache experiment: the cache service is switched off

Measured on run 527 and it cannot work. Every actions/cache step on these
runners prints

  Cache action is only supported on GHES version >= 3.5 ... check with
  GHES admin if Actions cache service is enabled or not

and then no-ops. The save step finishes in 0.19-0.31s, which is not a
few hundred megabytes of .debs going anywhere. setup-php timings were
unchanged against the run 526 baseline, within the usual variance:
8.3 454s then 148s, 8.5 733s then 446s, both noise rather than signal.

The same warning appears on the Composer cache this workflow has carried
all along, including run 523 and earlier, so that step has never cached
anything either. Worth fixing, but in the runner config rather than here.

Leaving dead steps in the workflow is how the Composer cache went years
without anyone noticing it did nothing, so the experiment comes out until
act_runner has its cache service enabled. It is in the history when that
happens. Detail in #178.

Co-Authored-By: Claude Opus 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01Uw545F1vveNJKjzLxdi2ks

.gitea/workflows/ci.yml

@@ -19,35 +19,6 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      # setup-php installs PHP 8.3+ through php-builder, which apt-installs ~70
-      # -dev packages before unpacking the build (#178). Ubuntu's own image
-      # deletes the .debs after install, so every job re-downloads them from
-      # the archive. Keep them and restore them from the cache server, which
-      # lives in the cluster, turning a WAN download into a local one.
-      #
-      # The dep list is the same for every PHP version on the builder path, so
-      # one shared key serves them all. Only the .debs are cached, never
-      # /var/lib/apt/lists — a stale index is how you get 404s on install.
-      - name: Keep downloaded .debs
-        run: |
-          sudo rm -f /etc/apt/apt.conf.d/docker-clean
-          echo 'Binary::apt::APT::Keep-Downloaded-Packages "true";' \
-            | sudo tee /etc/apt/apt.conf.d/99keep-downloaded-packages >/dev/null
-
-      - name: Cache apt packages
-        uses: actions/cache@v3
-        with:
-          path: /var/cache/apt/archives/*.deb
-          key: apt-php-builder-deps-${{ runner.arch }}-v1
-
-      # Temporary, for #178: shows whether the cache actually served the
-      # builder's dependencies, and times the step that consumes them.
-      - name: Report restored .debs
-        run: |
-          echo "restored .debs: $(ls /var/cache/apt/archives/*.deb 2>/dev/null | wc -l)"
-          echo "restored size:  $(du -sh /var/cache/apt/archives 2>/dev/null | cut -f1)"
-          date -u +'setup-php start: %H:%M:%S'
-
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
         with:
@@ -83,35 +54,6 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      # setup-php installs PHP 8.3+ through php-builder, which apt-installs ~70
-      # -dev packages before unpacking the build (#178). Ubuntu's own image
-      # deletes the .debs after install, so every job re-downloads them from
-      # the archive. Keep them and restore them from the cache server, which
-      # lives in the cluster, turning a WAN download into a local one.
-      #
-      # The dep list is the same for every PHP version on the builder path, so
-      # one shared key serves them all. Only the .debs are cached, never
-      # /var/lib/apt/lists — a stale index is how you get 404s on install.
-      - name: Keep downloaded .debs
-        run: |
-          sudo rm -f /etc/apt/apt.conf.d/docker-clean
-          echo 'Binary::apt::APT::Keep-Downloaded-Packages "true";' \
-            | sudo tee /etc/apt/apt.conf.d/99keep-downloaded-packages >/dev/null
-
-      - name: Cache apt packages
-        uses: actions/cache@v3
-        with:
-          path: /var/cache/apt/archives/*.deb
-          key: apt-php-builder-deps-${{ runner.arch }}-v1
-
-      # Temporary, for #178: shows whether the cache actually served the
-      # builder's dependencies, and times the step that consumes them.
-      - name: Report restored .debs
-        run: |
-          echo "restored .debs: $(ls /var/cache/apt/archives/*.deb 2>/dev/null | wc -l)"
-          echo "restored size:  $(du -sh /var/cache/apt/archives 2>/dev/null | cut -f1)"
-          date -u +'setup-php start: %H:%M:%S'
-
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
         with:
@@ -155,35 +97,6 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      # setup-php installs PHP 8.3+ through php-builder, which apt-installs ~70
-      # -dev packages before unpacking the build (#178). Ubuntu's own image
-      # deletes the .debs after install, so every job re-downloads them from
-      # the archive. Keep them and restore them from the cache server, which
-      # lives in the cluster, turning a WAN download into a local one.
-      #
-      # The dep list is the same for every PHP version on the builder path, so
-      # one shared key serves them all. Only the .debs are cached, never
-      # /var/lib/apt/lists — a stale index is how you get 404s on install.
-      - name: Keep downloaded .debs
-        run: |
-          sudo rm -f /etc/apt/apt.conf.d/docker-clean
-          echo 'Binary::apt::APT::Keep-Downloaded-Packages "true";' \
-            | sudo tee /etc/apt/apt.conf.d/99keep-downloaded-packages >/dev/null
-
-      - name: Cache apt packages
-        uses: actions/cache@v3
-        with:
-          path: /var/cache/apt/archives/*.deb
-          key: apt-php-builder-deps-${{ runner.arch }}-v1
-
-      # Temporary, for #178: shows whether the cache actually served the
-      # builder's dependencies, and times the step that consumes them.
-      - name: Report restored .debs
-        run: |
-          echo "restored .debs: $(ls /var/cache/apt/archives/*.deb 2>/dev/null | wc -l)"
-          echo "restored size:  $(du -sh /var/cache/apt/archives 2>/dev/null | cut -f1)"
-          date -u +'setup-php start: %H:%M:%S'
-
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
         with: