Fix the version passed to the image

Contrary to what internet resources say, ${{github.event.ref}} also contains the `ref/tags/` prefix. That is removed now.

Also, setting the version with plain "-X version.Version" does not seem to work consistently. Adding the full package as a prefix fixes this.

Dockerfile

@@ -16,7 +16,7 @@ ARG operator_version=dev
 RUN CGO_ENABLED=0 \
     GO111MODULE=on \
     go build \
-    -ldflags "-X version.Version=$operator_version" \
+    -ldflags "-X \"github.com/1Password/onepassword-operator/version.Version=$operator_version\"" \
     -mod vendor \
     -a -o manager main.go