Add act-test-runner package to the list of integrations (#49)

Author: pshevche

src/integrations.md

@@ -4,5 +4,5 @@
 
 - [Gitea Actions runner](https://gitea.com/gitea/act_runner)
 - [github-act-runner](https://github.com/ChristopherHX/github-act-runner)
-- [Gradle Act plugin](https://github.com/pshevche/gradle-act-plugin)
+- [act-test-runner](https://github.com/pshevche/act-test-runner)
 - [GitHub Local Actions for Visual Studio Code](https://sanjulaganepola.github.io/github-local-actions-docs/)