Add src/i18n-cache to CI caches

.buildkite/commands/install-node-dependencies.sh

@@ -3,15 +3,20 @@
 PLATFORM=$(uname -s)
 ARCHITECTURE=$(uname -m)
 NODE_VERSION=$(node --version)
+
 PACKAGE_HASH=$(hash_file package-lock.json)
 GUTENBERG_PACKAGE_HASH=$(hash_file gutenberg/package-lock.json)
-JETPACK_PACKAGE_HASH=$(hash_file jetpack/pnpm-lock.yaml)
 CACHEKEY="$BUILDKITE_PIPELINE_SLUG-npm-$PLATFORM-$ARCHITECTURE-node$NODE_VERSION-$PACKAGE_HASH-$GUTENBERG_PACKAGE_HASH"
+
+JETPACK_PACKAGE_HASH=$(hash_file jetpack/pnpm-lock.yaml)
 PNPM_CACHEKEY="$BUILDKITE_PIPELINE_SLUG-pnpm-$PLATFORM-$ARCHITECTURE-node$NODE_VERSION-$JETPACK_PACKAGE_HASH"
 
+I18N_CACHEKEY="$BUILDKITE_PIPELINE_SLUG-i18n-$PLATFORM-$ARCHITECTURE-node$NODE_VERSION-$PACKAGE_HASH-$GUTENBERG_PACKAGE_HASH"
+
 echo "--- :npm: Restore cache if present"
 restore_cache "$CACHEKEY"
 restore_cache "$PNPM_CACHEKEY"
+restore_cache "$I18N_CACHEKEY"
 
 echo "--- :npm: Install Node dependencies"
 npm ci --unsafe-perm --prefer-offline --no-audit --no-progress "$@"
@@ -21,6 +26,7 @@ echo "--- :npm: Save cache if necessary"
 # Those get regenerated by npm ci as per Node reccomendations.
 # What we are caching is the root npm folder, which stores pacakge downloads so they are available if the package.json resolution demands them.
 save_cache "$HOME/.npm" "$CACHEKEY"
+save_cache src/i18n-cache "$I18N_CACHEKEY"
 
 # If we attempted to save the pnpm cache when npm run with '--prefix gutenberg', the command might fail.
 # That's because the Jetpack submodule alone uses pnpm.