chore: add github workflows to sonar.exclusions

[batchu5]

Adds the github workflows to sonar.exclusions in the file .sonarcloud.properties Fixes #603

[sonarqubecloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[batchu5]

@princerajpoot20 please check it once

[princerajpoot20]

@batchu5 Thanks for your effort. I have fixed this issue in the .github repo that manages our workflows centrally. FYR: https://github.com/asyncapi/.github/pull/365 Hence, we now don't need to fix them in every downstream repo.

You can go ahead and close this PR

Thanks again for you effort!