feat: save storage secrets

[olevski]

Migrating
SwissDataScienceCenter/renku-notebooks#1927

Depends on #566 and #565

Also will keep this as draft and resolve/merge only when the new data connectors code and secrets that @leafty is working on is merged.

[Panaetius]

would this be a good time to switch to direct calls in code instead of calling the data svc REST api from within data svc?

[coveralls]

Pull Request Test Coverage Report for Build 12253840387

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 22 of 61 (36.07%) changed or added relevant lines in 6 files are covered.
• 8 unchanged lines in 5 files lost coverage.
• Overall coverage increased (+0.07%) to 85.785%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
components/renku_data_services/notebooks/api/classes/k8s_client.py	6	12	50.0%
components/renku_data_services/notebooks/api/classes/data_service.py	2	10	20.0%
components/renku_data_services/notebooks/api/schemas/cloud_storage.py	1	11	9.09%
components/renku_data_services/notebooks/core.py	6	21	28.57%

Files with Coverage Reduction	New Missed Lines	%
components/renku_data_services/notebooks/api/classes/data_service.py	1	33.33%
components/renku_data_services/notebooks/api/schemas/cloud_storage.py	1	35.96%
components/renku_data_services/notebooks/api/classes/k8s_client.py	2	64.91%
components/renku_data_services/storage/blueprints.py	2	95.69%
components/renku_data_services/storage/models.py	2	84.11%

Totals
Change from base Build 12253732488:	0.07%
Covered Lines:	14556
Relevant Lines:	16968

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💛 - Coveralls