Bump mysql-connector-java from 8.0.29 to 8.0.30 in /modules/tidb

Bumps [mysql-connector-java](https://github.com/mysql/mysql-connector-j) from 8.0.29 to 8.0.30.
- [Release notes](https://github.com/mysql/mysql-connector-j/releases)
- [Changelog](https://github.com/mysql/mysql-connector-j/blob/release/8.0/CHANGES)
- [Commits](mysql/mysql-connector-j@8.0.29...8.0.30)

---
updated-dependencies:
- dependency-name: mysql:mysql-connector-java
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

modules/tidb/build.gradle

@@ -4,7 +4,7 @@ dependencies {
     api project(':jdbc')
 
     testImplementation project(':jdbc-test')
-    testImplementation 'mysql:mysql-connector-java:8.0.29'
+    testImplementation 'mysql:mysql-connector-java:8.0.30'
 
     compileOnly 'org.jetbrains:annotations:23.0.0'
 }