Bump mysql-connector-java from 5.1.6 to 8.0.16 in /sample-tom

Bumps [mysql-connector-java](https://github.com/mysql/mysql-connector-j) from 5.1.6 to 8.0.16.
- [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/5.1.6...8.0.16)
Signed-off-by: Ndependabot[bot] <support@github.com>

sample-tom/pom.xml

@@ -16,7 +16,7 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
         <java.version>1.8</java.version>
-        <mysql.version>5.1.6</mysql.version>
+        <mysql.version>8.0.16</mysql.version>
     </properties>
 
     <dependencies>