(2.1.x): Bump org.wiremock:wiremock-standalone from 3.8.0 to 3.9.0

Bumps [org.wiremock:wiremock-standalone](https://github.com/wiremock/wiremock) from 3.8.0 to 3.9.0.
- [Release notes](https://github.com/wiremock/wiremock/releases)
- [Commits](wiremock/wiremock@3.8.0...3.9.0)

---
updated-dependencies:
- dependency-name: org.wiremock:wiremock-standalone
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

build.gradle

@@ -24,7 +24,7 @@ buildscript {
 		immutablesVersion = "2.10.1"
 		openServiceBrokerVersion = "4.1.2"
 		springFrameworkVersion = "6.0.0"
-		wiremockVersion = "3.8.0"
+		wiremockVersion = "3.9.0"
 	}
 }