feat: optional base64 encoding for local cred #503

Job	Run time
Collect changes / collect-changes	6s
Python tests / lint-and-format-check	37s
Python tests / unit-tests (py313)	2m 52s
Python tests / types-check	1m 7s
Python tests / unit-tests (py312)	6m 7s
Python tests / unit-tests (py311)	2m 22s
Python tests / unit-tests (py310)	2m 15s
Python tests / unit-tests (py39)	2m 35s
status-check	2s
	18m 3s

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