Update README.md: Add Contribution Tutorial Link

[melonatwork]

In this commit I added a link to the contribution tutorial on the documentation to gain a contributor better access to this site.

Pre-flight checklist

• I have read the Contributing Guidelines on pull requests.
• If this is a code change: I have written unit tests and/or added dogfooding pages to fully verify the new behavior.
• If this is a substantial change: the PR has an accompanying issue (closes #0000) and the maintainers have approved on my working plan.

Motivation

Its better

[TheMelone2]

Seems good to me.