CI: fix ci pipeline if not triggered by pr

[glorv]

What problem does this PR solve?

fix ci pipeline scripts

What is changed and how it works?

Fix for git checkout refSpec if build is not triggered by github pr

Check List

Tests

• Unit test
• Integration test

[glorv]

/run-all-tests

[glorv]

/run-integration-tests

[july2993]

/run-all-tests

[CLAassistant]

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1 out of 2 committers have signed the CLA.

✅ july2993
❌ glorv
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[sre-bot]

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