Add script to apply release-only changes

scripts/release/apply-release-changes.sh

@@ -0,0 +1,53 @@
+#!/usr/bin/env bash
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+: '
+# Step 2 after branch cut is complete.
+#
+# Creates PR with release only changes.
+#
+# Usage (run from root of project):
+#  DRY_RUN=disabled ./scripts/release/apply-release-changes.sh
+#
+# RELEASE_VERSION: Version of this current release
+'
+
+set -eou pipefail
+
+GIT_TOP_DIR=$(git rev-parse --show-toplevel)
+RELEASE_VERSION=${RELEASE_VERSION:-$(cut -d'.' -f1-2 "${GIT_TOP_DIR}/version.txt")}
+RELEASE_BRANCH="release/${RELEASE_VERSION}"
+
+# Check out to Release Branch
+
+if git ls-remote --exit-code origin ${RELEASE_BRANCH} >/dev/null 2>&1; then
+  echo "Check out to Release Branch '${RELEASE_BRANCH}'"
+  git checkout -b ${RELEASE_BRANCH}
+else
+  echo "Error: Remote branch '${RELEASE_BRANCH}' not found. Please run 'cut-release-branch.sh' first."
+  exit 1
+fi
+
+# Change all GitHub Actions to reference the test-infra release branch
+# as opposed to main.
+echo "Applying release-only changes to workflows"
+for i in .github/workflows/*.yml; do
+  if [[ "$OSTYPE" == "darwin"* ]]; then
+    sed -i '' -e s#@main#@"${RELEASE_BRANCH}"# $i;
+    sed -i '' -e s#test-infra-ref:[[:space:]]main#"test-infra-ref: ${RELEASE_BRANCH}"# $i;
+  else
+    sed -i -e s#@main#@"${RELEASE_BRANCH}"# $i;
+    sed -i -e s#test-infra-ref:[[:space:]]main#"test-infra-ref: ${RELEASE_BRANCH}"# $i;
+  fi
+done
+
+echo "You'll need to manually commit the changes and create a PR. Here are the steps:"
+echo "1. Stage the changes to the workflow files:"
+echo "   git add ./github/workflows/*.yml"
+echo "2. Commit the changes:"
+echo "   git commit -m \"[RELEASE-ONLY CHANGES] Branch Cut for Release ${RELEASE_VERSION}\""
+echo "3. After committing, create a pull request to merge the changes."