.bazelci/presubmit.yml: run BCR tests with multiple Bazel versions (#4490)

**What type of PR is this?**

> Test

**What does this PR do? Why is it needed?**

On presubmit, run the BCR test with multiple Bazel versions. This helps
us
catch issues before a release.

**Which issues(s) does this PR fix?**

n/a

**Other notes for review**

Author: jayconrod

.bazelci/presubmit.yml

@@ -2,8 +2,13 @@
 matrix:
   platform:
     - ubuntu2404
+    - ubuntu2004_arm64
     - macos_arm64
     - windows
+  # Only BCR tests use all Bazel versions. Others use the default.
+  bazel:
+    - 7.x
+    - 8.x
 
 tasks:
   debian11_bazel6:
@@ -63,6 +68,7 @@ tasks:
   bcr_tests:
     name: BCR test module
     platform: ${{ platform }}
+    bazel: ${{ bazel }}
     working_directory: tests/bcr
     build_flags:
       - "--allow_yanked_versions=all"