Bump assertj-core from 3.12.2 to 3.18.1

Bumps [assertj-core](https://github.com/assertj/assertj-core) from 3.12.2 to 3.18.1.
- [Release notes](https://github.com/assertj/assertj-core/releases)
- [Commits](assertj/assertj@assertj-core-3.12.2...assertj-core-3.18.1)

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

build.gradle

@@ -70,7 +70,7 @@ dependencies {
   testCompile group: 'org.junit.jupiter', name: 'junit-jupiter-engine', version: '5.4.1'
   testCompile group: 'org.junit.jupiter', name: 'junit-jupiter-api', version: '5.4.1'
   testCompile group: 'org.junit.jupiter', name: 'junit-jupiter-params', version: '5.4.1'
-  testCompile group: 'org.assertj', name: 'assertj-core', version: '3.12.2'
+  testCompile group: 'org.assertj', name: 'assertj-core', version: '3.18.1'
   testCompile group: 'org.mockito', name: 'mockito-core', version: '3.6.28'
   testCompile group: 'org.jsoup', name: 'jsoup', version: '1.10.2'
   testCompile group: 'cd.go.plugin', name: 'go-plugin-api', version: '20.10.0'