fix: Remove duplicate text in CONTRIBUTING.md

[eyewritecode]

Checklist

• I have made a material change to the repo (functionality, testing, spelling, grammar)
• I have read the [Contribution Guide] and my PR follows them.
• I updated my branch with the master branch.
• [N/A] I have added tests that prove my fix is effective or that my feature works
• [N/A] I have added necessary documentation about the functionality in the appropriate .md file
• [N/A] I have added in line documentation to the code I modified

Short description of what this PR does:

• This PR removes the duplicate text found in the CONTRIBUTING.md file

[thinkingserious]

Hello @eyewritecode,

Thanks again for the PR!

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