fix readme & bump mysqlclient (#3)

* fix readme & bump mysqlclient

* fix ci

Author: wd0517

.github/workflows/test.yml

@@ -31,6 +31,8 @@ jobs:
         run: |
           python -m pip install --upgrade pip
           python -m pip install -r requirements.txt
+      - name: Wait for tidb to start
+        run: sleep 20
       - name: Run tests
         run: |
           python mysqlclient_example.py > temp

README-zh.md

@@ -7,7 +7,7 @@
 
 ## 前置要求
 
-- 推荐 [Python 3.10 及以上版本](https://www.python.org/downloads/)
+- 推荐 [Python 3.8 及以上版本](https://www.python.org/downloads/)
 - [Git](https://git-scm.com/downloads)
 - TiDB 集群。如果你还没有 TiDB 集群，可以按照以下方式创建：
   - （推荐方式）参考[创建 TiDB Serverless 集群](https://docs.pingcap.com/tidbcloud/dev-guide-build-cluster-in-cloud)，创建你自己的 TiDB Cloud 集群。

README.md

@@ -7,7 +7,7 @@ This a sample project written by PingCAP for mysqlcient to connect to TiDB.
 
 ## Prerequisites
 
-- [Python 3.10 or higher](https://www.python.org/downloads/)
+- [Python 3.8 or higher](https://www.python.org/downloads/)
 - [Git](https://git-scm.com/downloads)
 - A TiDB cluster. If you don't have a TiDB cluster, you can create one as follows:
   - (Recommended) Follow [Creating a TiDB Serverless Cluster](https://docs.pingcap.com/tidbcloud/dev-guide-build-cluster-in-cloud) to create your own TiDB Cloud cluster.

requirements.txt

@@ -1,2 +1,2 @@
-mysqlclient==2.2.0
+mysqlclient==2.2.1
 python-dotenv==1.0.0