fix(make): explicit integration test timeout + single race switch (#5151)

with a cold fixture cache the integration suite builds and saves 18 docker
images across 36 sequential tests, which walks past `go test`'s default 10m
timeout and takes the fixture cache rebuild down with it. that suite now runs
`go test` directly with `-timeout=30m` (gotest.Tasks() has no timeout option),
plus `-count=1` since the built fixtures are the side effect we're actually
after and a test cache hit would skip producing them.

also adds `RACE` as one switch for the race detector across every suite:

- `RACE=false make test` drops `-race` from unit + integration and skips the
  race smoke, worth doing on a cache rebuild where the wall clock is all
  docker builds anyway
- `RACE=true` forces it on locally
- unset behaves as before: on in CI, off locally and on windows

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

Taskfile.yaml

@@ -125,6 +125,7 @@ tasks:
     desc: Run tests for pipeline utils
     cmds:
       - cmd: .github/scripts/labeler_test.py
+      - cmd: go test -C .make ./...
 
   snapshot-smoke-test:
     desc: Run a smoke test on the snapshot builds + docker images