Fix docs for adding ssh key for commit signing

[shuklaayush]

The config command expects a path to the private/public key and needs to be prefixed with key:: when using the public key directly ref: https://git-scm.com/docs/git-config#Documentation/git-config.txt-usersigningKey

Why:

Closes 20114

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[cmwilson21]

@shuklaayush thanks for opening a PR! It looks like someone opened an issue about this yesterday, so I'm going to edit your post to link the two of them together.

I'll get this triaged for review! ⚡

[0649044724]

ทำไม่เป็นคนแบบนี้เห็นแกได้ประโยคของคนอื่น

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