[CI] Add new entries to skip triggering Buildkite builds (#13982)

Allow also to skip triggering Buildkite builds if Pull Requests just update
.buildkite/pull-requests.json or catalog-info.yaml. This also applies when
checking for non-package files modified to select which packages are tested.

Author: mrodm

.buildkite/pull-requests.json

@@ -13,7 +13,7 @@
       "always_trigger_comment_regex": "^(?:(?:buildkite\\W+)?(?:build|test)\\W+(?:this|it))|^/test$|^/test benchmark fullreport$",
       "skip_ci_labels": [],
       "skip_target_branches": [],
-      "skip_ci_on_only_changed": ["^.github/workflows/", "^.github/dependabot.yml", "^.github/ISSUE_TEMPLATE/", "^docs/"],
+      "skip_ci_on_only_changed": ["^.github/workflows/", "^.github/dependabot.yml$", "^.github/ISSUE_TEMPLATE/", "^docs/", "^catalog-info.yaml$", "^.buildkite/pull-requests.json$"],
       "always_require_ci_on_changed": []
     },
     {

.buildkite/scripts/common.sh

@@ -746,7 +746,7 @@ is_pr_affected() {
     # Example:
     # https://buildkite.com/elastic/integrations/builds/25606
     # https://github.com/elastic/integrations/pull/13810
-    if git diff --name-only "${commit_merge}" "${to}" | grep -E -v '^(packages/|\.github/(CODEOWNERS|ISSUE_TEMPLATE|PULL_REQUEST_TEMPLATE)|README\.md|docs/)' > /dev/null; then
+    if git diff --name-only "${commit_merge}" "${to}" | grep -E -v '^(packages/|\.github/(CODEOWNERS|ISSUE_TEMPLATE|PULL_REQUEST_TEMPLATE)|README\.md|docs/|catalog-info\.yaml|\.buildkite/pull-requests\.json)' > /dev/null; then
         echo "[${package}] PR is affected: found non-package files"
         return 0
     fi