[Utility] Update E2E feature path template doc

[adshmh]

Description

A brief summary of the expected contribution steps to improve the PRs opened by new team members.

Summary generated by Reviewpad on 06 Jul 23 00:42 UTC

This pull request includes the following changes:

1. In the .github/PULL_REQUEST_TEMPLATE.md file, added a comment block to list out all the changes made in the pull request.
2. In the utility/doc/E2E_FEATURE_PATH_TEMPLATE.md file, added a link to a potential example to use in the improvement section.
3. Updated the E2E Feature Implementation section with a TL;DR summary and steps for making the E2E test pass.
4. Added goals for the POC (Proof of Concept) section and provided an example PR with added .feature and .go files.
5. Added a link to Alessandro's KISS or Bryan's P2P in the MVC: Minimum Viable Change section.

Overall, this pull request includes improvements and additions to the pull request template and the E2E feature path documentation.

Issue

Minimize the number of large PRs, e.g. #789, which take longer to review and are more error-prone.

Type of change

Please mark the relevant option(s):

• [ ] New feature, functionality or library
• [ ] Bug fix
• [ ] Code health or cleanup
• [ ] Major breaking change
• [X] Documentation
• [ ] Other

List of changes

• Added a new CONTRIBUTING.md file under utility module's docs.

Testing

N/A

Required Checklist

N/A

If Applicable Checklist

• [ ] I have updated the corresponding README(s); local and/or global
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] I have added, or updated, mermaid.js diagrams in the corresponding README(s)
• [X] I have added, or updated, documentation and mermaid.js diagrams in shared/docs/* if I updated shared/*README(s)

[adshmh]

Please consider the suggestion I made and then feel free to merge!

Thank you for the review. PR updated. Will merge once CI checks pass.