Bump mysql-connector-java from 5.1.25 to 8.0.28 in /rackspace

Bumps [mysql-connector-java](https://github.com/mysql/mysql-connector-j) from 5.1.25 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/5.1.25...8.0.28)

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

Signed-off-by: dependabot[bot] <support@github.com>
diff --git a/rackspace/pom.xml b/rackspace/pom.xml
index 2557e34..9117b9b 100644
--- a/rackspace/pom.xml
+++ b/rackspace/pom.xml
@@ -162,7 +162,7 @@
     <dependency>
       <groupId>mysql</groupId>
       <artifactId>mysql-connector-java</artifactId>
-      <version>5.1.25</version>
+      <version>8.0.28</version>
     </dependency>
     <dependency>
       <groupId>com.google.auto.service</groupId>