chore(deps): update ruby docker tag

This MR contains the following updates:

Package	Type	Update	Change
ruby (source)		minor	3.0.1 -> 3.1.2
ruby		major	2.7.6 -> 3.1.2
ruby		minor	3.0.3 -> 3.1.2
ruby	image	major	2.7.6-alpine -> 3.1.2-alpine
ruby	image	major	2.7-alpine -> 3.1-alpine
ruby	image	patch	3.1.1-alpine -> 3.1.2-alpine

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