chore: upgrade default helm version to 3.15.1

[johnkrzywanek]

Upgrade helm version with bug fixes, especially needed for: https://github.com/helm/helm/issues/12835

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[jenkins-x-bot]

Hi @johnkrzywanek. Thanks for your PR.

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[johnkrzywanek]

/assign @jordangoasdoue

[msvticket]

/ok-to-test

[JordanGoasdoue]

/approve

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