bcr_presubmit: Use Rocky Linux instead of CentOS (#2314)

Some module repos still contain presubmit.yml templates that reference
CentOS 7 (which has been deprecated in favor of Rocky Linux 8).
Eventually we should remove all these references, but for now we can
work around this problem by replacing centos7 tasks with their
rockylinux8 equivalent during presubmit.

Progress towards
#2272

Author: fweikert

buildkite/bazel-central-registry/bcr_presubmit.py

@@ -135,7 +135,7 @@ def get_test_module_task_config(module_name, module_version, bazel_version=None)
 
 def add_presubmit_jobs(module_name, module_version, task_configs, pipeline_steps, is_test_module=False, overwrite_bazel_version=None, calc_concurrency=None):
     for task_id, task_config in task_configs.items():
-        platform_name = bazelci.get_platform_for_task(task_id, task_config)
+        platform_name = get_platform(task_id, task_config)
         platform_label = bazelci.PLATFORMS[platform_name]["emoji-name"]
         task_name = task_config.get("name", "")
         label = f"{module_name}@{module_version} - {platform_label} - {task_name}"
@@ -165,6 +165,13 @@ def add_presubmit_jobs(module_name, module_version, task_configs, pipeline_steps
         pipeline_steps.append(bazelci.create_step(label, commands, platform_name, concurrency=concurrency, concurrency_group=concurrency_group))
 
 
+def get_platform(task_id, task_config):
+    original = bazelci.get_platform_for_task(task_id, task_config)
+    # TODO(#2272): delete once centos references have been deleted
+    # from BCR templates in all module repos.
+    return original.replace("centos7", "rockylinux8")
+
+
 def scratch_file(root, relative_path, lines=None, mode="w"):
     """Creates a file under the root directory"""
     if not relative_path: