fix: do not pass awaitable in __get_gitlab_image_pull_secret

[leafty]

Closes #1082.

/deploy

[RenkuBot]

You can access the deployment of this PR at https://renku-ci-ds-1083.dev.renku.ch

[coveralls]

Pull Request Test Coverage Report for Build 18840025735

Details

• 1 of 3 (33.33%) changed or added relevant lines in 1 file are covered.
• 4 unchanged lines in 3 files lost coverage.
• Overall coverage increased (+0.03%) to 86.84%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
components/renku_data_services/notebooks/core_sessions.py	1	3	33.33%

Files with Coverage Reduction	New Missed Lines	%
components/renku_data_services/crc/core.py	1	77.96%
components/renku_data_services/notebooks/util/retries.py	1	59.38%
components/renku_data_services/storage/blueprints.py	2	92.68%

Totals
Change from base Build 18746754278:	0.03%
Covered Lines:	22727
Relevant Lines:	26171

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💛 - Coveralls

[RenkuBot]

Tearing down the temporary RenkuLab deployment for this PR.