standardize the use of a prestart.sh script inside test_collections

prestart.sh

@@ -24,5 +24,10 @@ alembic upgrade head
 # Create initial data in DB
 python ./app/initial_data.py
 
-# Update SDK Tests (YAML and Python Tests)
-./test_collections/sdk_tests/fetch_sdk_tests_and_runner.sh
+# Run Prestart scripts in test collections
+for dir in ./test_collections/*
+do
+    prestart=$dir/prestart.sh
+    # Only run prestart.sh if present/
+    [ -x $prestart ] && $prestart
+done

test_collections/sdk_tests/prestart.sh

@@ -0,0 +1,23 @@
+#! /usr/bin/env bash
+
+ #
+ # Copyright (c) 2023 Project CHIP Authors
+ #
+ # 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.
+
+ # Paths
+SDK_TESTS_DIR=$(dirname "$0")
+cd $SDK_TESTS_DIR
+
+# Fetch code from SDK
+./scripts/fetch_sdk_tests_and_runner.sh