Update contrib files to replace CNCF references

[GeauxJD]

Describe your changes

Updates contributing documentation to replace CNCF references with OpenSSF

Related issue number or link (ex: resolves #issue-number)

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• This PR does not contain plagiarism
  • don’t copy other people’s work unless you are quoting and contributing it to them.
• I have signed off on all commits
  • signing off (ex: git commit -s) is to affirm that commits comply DCO. If you are working locally, you could add an alias to your gitconfig by running git config --global alias.ci "commit -s".