ci: run goreleaser without the runner's GOCACHEPROG

goreleaser runs several go builds at once; each spawns its own gobuildcache,
and they time out on its per-entry file locks while one holds the lock
across a slow S3 call ('failed to acquire lock: context deadline exceeded',
check-release on #997). Use Go's local cache for goreleaser.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Ma8eHhW59hLAJuLzBnLvUu

.gitea/workflows/ci.yaml

@@ -61,11 +61,15 @@ jobs:
         with:
           version: '~> v2'
           args: check
-      - name: Test release build
+      - name: Install goreleaser
         uses: goreleaser/goreleaser-action@v7
         with:
           version: '~> v2'
-          args: release --snapshot --clean
+          install-only: true
+      # Without the runner's GOCACHEPROG (gobuildcache): goreleaser's parallel
+      # go builds contend for its per-entry locks and time out.
+      - name: Test release build
+        run: env -u GOCACHEPROG goreleaser release --snapshot --clean
 
   build:
     needs: [check, vulnerabilities, check-release]

.gitea/workflows/goreleaser.yaml

@@ -27,4 +27,5 @@ jobs:
         run: |
           GITEA_TOKEN=$(cat "${RELEASE_TOKEN_FILE}")
           export GITEA_TOKEN
-          goreleaser release --clean
+          # Without GOCACHEPROG: parallel builds contend for gobuildcache's locks.
+          env -u GOCACHEPROG goreleaser release --clean