[CI] Adding url link to cdash webpages

[YanzhaoW]

In the end of CI workflow (tab ctest-cdash), there will be two url links to the gsi cdash website.

    Submission successful
--  CDash Build Summary ..: https://cdash.gsi.de/buildSummary.php?buildid=391787
--  CDash Test List ......: https://cdash.gsi.de/viewTest.php?buildid=391787

Adapted from FairRoot CI workflow.

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Checklist:

• [x] Rebased against dev branch
• [x] My name is in the resp. CONTRIBUTORS/AUTHORS file
• [x] Followed the pull request guidlines and the Git workflow
• [x] Followed the seven rules of great commit messages