Avoid backticks in AI-generated Git commit messages

[melkstam]

This fixes an issue where the AI-generated git commit message includes backticks around the message itself.

Release Notes:

• Fixed an issue where the AI-generated git commit message would include backticks around the message itself

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[melkstam]

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[maxdeviant]

Thanks for the PR!

We'll need to get the commit message prompt under our eval framework before making any changes to the prompt, so that we can verify them.