Improved the logging and notification system in the Jenkins pipeline

[Pranjal0410]

Improved the logging and notification system in the Jenkins pipeline to provide clearer feedback during the build process. This can help users quickly identify issues and understand the build status.

In the runTests.sh and runKernelTests.sh scripts, enhance error handling and logging to provide more context when failures occur.

[welcome[bot]]

Thanks for opening this pull request! Now continious integration (CI) will build Pharo with your change and run all tests. This might fail due to many reasons! Please check if your PR breaks the build or makes tests fail. Feel free to add comments to the PR. After this, before your PR can be merged it needs one or more reviews. Do not hesitate to ask people (on the Mailinglist or Discord) to help! When the CI shows no problems and there are positive reviews, your PR will be merged.