Bump mysql-connector-java in /frameworks/Java/rapidoid

Bumps [mysql-connector-java](https://github.com/mysql/mysql-connector-j) from 8.0.18 to 8.0.28.
- [Release notes](https://github.com/mysql/mysql-connector-j/releases)
- [Changelog](https://github.com/mysql/mysql-connector-j/blob/release/8.0/CHANGES)
- [Commits](https://github.com/mysql/mysql-connector-j/compare/8.0.18...8.0.28)

---
updated-dependencies:
- dependency-name: mysql:mysql-connector-java
  dependency-type: direct:production
...

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

frameworks/Java/rapidoid/pom.xml

@@ -23,7 +23,7 @@
 		<dependency>
 			<groupId>mysql</groupId>
 			<artifactId>mysql-connector-java</artifactId>
-			<version>8.0.18</version>
+			<version>8.0.28</version>
 		</dependency>
 		<dependency>
 			<groupId>org.postgresql</groupId>