bazel: Bump version -> 7.4.0 (#37864)

the current bazel version is flakey and is triggering at least one build
issue for downstreams

the only reason we are using it is due to broken env vars in later
versions that fails our mobile/coverage ci

this PR bumps the version to 7.x latest and worksaround the
mobile/coverage issue by injecting the known working bazel version for
that ci alone

Fix #37857 
Fix #37852

Signed-off-by: Ryan Northey <[email protected]>

Author: phlax

.bazelversion

@@ -1 +1 @@
-7.1.2
+7.4.0

.github/workflows/mobile-coverage.yml

@@ -58,6 +58,13 @@ jobs:
           run: |
             cd mobile
             tar -czf coverage.tar.gz generated/coverage
+      # TODO(phlax): This is a highly undesirable workaround - remove once
+      #   https://github.com/bazelbuild/bazel/issues/23247 is resolved/available
+      steps-pre: |
+        - name: Inject bazel version
+          shell: bash
+          run: |
+            echo "7.1.2" > .bazelversion
       target: mobile-coverage
       timeout-minutes: 120
       upload-name: coverage.tar.gz