Bump mysql-connector-java from 8.0.27 to 8.0.28 in /modules/spock

Bumps [mysql-connector-java](https://github.com/mysql/mysql-connector-j) from 8.0.27 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](mysql/mysql-connector-j@8.0.27...8.0.28)

---
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/spock/build.gradle

@@ -16,7 +16,7 @@ dependencies {
     testImplementation 'org.apache.httpcomponents:httpclient:4.5.13'
 
     testRuntimeOnly 'org.postgresql:postgresql:42.3.1'
-    testRuntimeOnly 'mysql:mysql-connector-java:8.0.27'
+    testRuntimeOnly 'mysql:mysql-connector-java:8.0.28'
 
     testCompileClasspath 'org.jetbrains:annotations:23.0.0'
 }