Bump org.spockframework:spock-core from 2.3-groovy-3.0 to 2.3-groovy-4.0

Bumps org.spockframework:spock-core from 2.3-groovy-3.0 to 2.3-groovy-4.0.

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

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

build.gradle

@@ -51,7 +51,7 @@ repositories {
 dependencies {
     implementation 'org.ow2.asm:asm:9.7.1'
 
-    testImplementation 'org.spockframework:spock-core:2.3-groovy-3.0'
+    testImplementation 'org.spockframework:spock-core:2.3-groovy-4.0'
 
     asciidoctorExt 'com.bmuschko:asciidoctorj-tabbed-code-extension:0.3'
 }