ci(integration): give the suite a 20m package timeout

internal/api takes ~6.5 min under -race on an idle runner; with a second
run on the same runner it crossed go test's default 10m (run 8368: FAIL
at 600.016s with the running test 2s old, so load, not a hang).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.gitea/workflows/release.yml

@@ -272,8 +272,12 @@ jobs:
           # every integration package TRUNCATEs the one shared test DB;
           # concurrent package binaries → TRUNCATE deadlocks. Serialize
           # package execution (the documented local invocation too).
+          # -timeout 20m: internal/api alone takes ~6.5 min under -race on
+          # an idle runner, and a dev and a main run sharing the runner
+          # pushed it past go test's default 10m (run 8368, 600.016s, the
+          # running test 2s old — nothing hung).
           MINSTREL_DATABASE_URL="$MINSTREL_TEST_DATABASE_URL" go run ./cmd/minstrel migrate
-          go test -p 1 -race ./...
+          go test -p 1 -race -timeout 20m ./...
 
   web:
     runs-on: go-ci