[CI] Add e2e test frame work and doctest (#730)

### What this PR does / why we need it?
Add quickstart doctest CI

### Does this PR introduce _any_ user-facing change?
no

### How was this patch tested?
- CI passed
- Run `/vllm-ascend/tests/e2e/run_doctests.sh`
Related: https://github.com/vllm-project/vllm-ascend/issues/725

Signed-off-by: Yikun Jiang <yikunkero@gmail.com>

tests/e2e/run_doctests.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+
+#
+# Copyright (c) 2025 Huawei Technologies Co., Ltd. All Rights Reserved.
+#
+# 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.
+# This file is a part of the vllm-ascend project.
+#
+
+set -eo errexit
+
+. $(dirname "$0")/common.sh
+
+_info "====> Start Quickstart test"
+. "${SCRIPT_DIR}/doctests/001-quickstart-test.sh"
+
+_info "Doctest passed."