ci: Pin google-quiche until main compiles again (#2573)

* ci: Pin `google-quiche` until `main` compiles again

Should fix the CI failures of the bencher.

* Again

Author: larseggert

.github/workflows/bench.yml

@@ -44,7 +44,7 @@ jobs:
         uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           repository: google/quiche
-          ref: main
+          ref: d42a7597517a574c1c71a4634b21b23852badf8c # FIXME: Switch back to main when that compiles again.
           path: gquiche
           submodules: true
           persist-credentials: false