feat(ci): upgrade ruby to 3.0.0

[sethkfman]

Development & PR Process

1. Follow MetaMask Mobile Coding Standards
2. Add release-xx label to identify the PR slated for a upcoming release (will be used in release discussion)
3. Add needs-dev-review label when work is completed
4. Add needs-qa label when dev review is completed
5. Add QA Passed label when QA has signed off

Description

This PR adds a ruby-version and Gemfile that enforces minimum versions of Ruby and cocoa pods.
Versions are set to:

• Ruby Version: 3.0.0
• Cocoapods Version: 1.12.1

Successful QA build: https://app.bitrise.io/build/39b514f5-4579-4e7a-bcbe-03945bc4860f

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Issue

Progresses #???

Checklist

• There is a related GitHub issue
• Tests are included if applicable
• Any added code is fully documented

[github-actions]

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[sethkfman]

Pending QA E2E build: https://app.bitrise.io/build/2befc39b-f2f3-43eb-8543-afe1d84da751

[Cal-L]

LGTM

[leotm]

just spotted the files introduced later in RN 0.67+ (nb: our 0.66.5)
https://github.com/facebook/react-native/blob/0.67-stable/template/Gemfile
https://github.com/facebook/react-native/blob/0.67-stable/template/_ruby-version
along with the Gem lockfile we didn't include
https://github.com/facebook/react-native/blob/0.67-stable/template/Gemfile.lock

presuming we're introducing these ahead for added security?
to prevent unmaintained Ruby v2.7 (EOL 31 Mar 2023) usage

edit: yeah makes sense, remembering now spotting the warning few mo ago

• Invalid hermes-engine.podspec file: undefined method `exists?' for File:Class facebook/react-native#35807 (comment)