Bump mysql-connector-java in /frameworks/Kotlin/ktor/ktor

Bumps [mysql-connector-java](https://github.com/mysql/mysql-connector-j) from 8.0.25 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/8.0.25...8.0.28)

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

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

frameworks/Kotlin/ktor/ktor/pom.xml

@@ -19,7 +19,7 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <hikaricp.version>5.0.0</hikaricp.version>
         <logback.version>1.2.4</logback.version>
-        <mysql.version>8.0.25</mysql.version>
+        <mysql.version>8.0.28</mysql.version>
         <postgresql.version>42.2.23</postgresql.version>
     </properties>