build: update python docker tag

This MR contains the following updates:

Package	Type	Update	Change
python	final	minor	3.9.7-alpine -> 3.10.0-alpine
python	stage	minor	3.9.7-alpine -> 3.10.0-alpine
python	final	minor	3.9-alpine -> 3.10-alpine
python	stage	minor	3.9-alpine -> 3.10-alpine

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