GitHub workflows are out of date

[mcmire]

The GitHub workflows in this repo do not align with the module template. Specifically, actions/cache is still being used in an unsafe manner (we should be using the checkout-and-setup action).

This should fix:

• https://github.com/MetaMask/create-release-branch/security/code-scanning/6
• https://github.com/MetaMask/create-release-branch/security/code-scanning/5
• https://github.com/MetaMask/create-release-branch/security/code-scanning/4

Acceptance Criteria

• .github/workflows in this repo matches the same directory in the module template.
• The Dependabot config should match the module template.
• The pull request template should match the module template (minus the final section).