This task includes setting up the testing framework for the kmp-project-template:
1. Adding multiplatform test libraries for commonTest source-sets like kotlin.test, Mokkery, etc.
2. Adding platform-specific dependencies for Android and IOS
3. Creating test-directories for cmp-shared, cmp-desktop, and cmp-ios. // move to different ticket
4. Create workflows for automated testing through CI/CD

add testing module in project home

Note: We should use only multiplatform-testing libraries for testing shared code.