💚 fix(pull_request): update link to contributing

[dylanmsql]

Pull request for Candy-doc

Your checklist for this pull request

🚨 Please review the guidelines for contributing to
this repository.

• Make sure you are requesting to pull a feature/bugfix branch (right
  side). Don't request your master!
• Make sure you are making a pull request against the main branch (left
  side).
• Check the commit's or even all commits' message styles matches our
  requested structure.
• Check your code additions will fail neither code linting checks nor unit
  test.

Description

Update link to contributing.md in pull_request_template.md.

❤️ Thank you!