Move gardener to GitHub actions

[dbadura]

Description

Changes proposed in this pull request:

• extract provisioning logic to github actions steps

Related issue(s)

[kyma-bot]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[kyma-bot]

@dbadura: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pre-serverless-runtimes-python312-build	17bbf14	link	false	/test pre-serverless-runtimes-python312-build
pre-serverless-runtimes-python39-build	17bbf14	link	false	/test pre-serverless-runtimes-python39-build

Full PR test history. Your PR dashboard.

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