Bump spock-bom from 2.2-groovy-4.0 to 2.3-groovy-4.0

Bumps spock-bom from 2.2-groovy-4.0 to 2.3-groovy-4.0.

---
updated-dependencies:
- dependency-name: org.spockframework:spock-bom
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

build.gradle

@@ -17,7 +17,7 @@ dependencies {
   // mandatory dependencies for using Spock
   implementation platform('org.apache.groovy:groovy-bom:4.0.5')
   implementation 'org.apache.groovy:groovy'
-  testImplementation platform("org.spockframework:spock-bom:2.2-groovy-4.0")
+  testImplementation platform("org.spockframework:spock-bom:2.3-groovy-4.0")
   testImplementation "org.spockframework:spock-core"
   testImplementation "org.spockframework:spock-junit4"  // you can remove this if your code does not rely on old JUnit 4 rules