chore: get publish docs build working with new release process (#11069)

internal/kokoro/trampoline_release.sh

@@ -0,0 +1,34 @@
+#!/bin/bash
+# Copyright 2024 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -eo pipefail
+# Always run the cleanup script, regardless of the success of bouncing into
+# the container.
+function cleanup() {
+    chmod +x ${KOKORO_GFILE_DIR}/trampoline_cleanup.sh
+    ${KOKORO_GFILE_DIR}/trampoline_cleanup.sh
+    echo "cleanup";
+}
+trap cleanup EXIT
+
+$(dirname $0)/populate-secrets.sh # Secret Manager secrets.
+TRAMPOLINE_HOST=$(echo "${TRAMPOLINE_IMAGE}" | cut -d/ -f1)
+if [[ ! "${TRAMPOLINE_HOST}" =~ "gcr.io" ]]; then
+  # If you need to specify a host other than gcr.io, you have to run on an update version of gcloud.
+  echo "TRAMPOLINE_HOST: ${TRAMPOLINE_HOST}"
+  gcloud components update
+  gcloud auth configure-docker "${TRAMPOLINE_HOST}"
+fi
+python3 "${KOKORO_GFILE_DIR}/trampoline_release.py"