Fix awkward wording in "cherry-pick" and "revert" errors.
This was originally in a WIP branch for #21812 (moved) but since it was moved into %Backlog I thought I'd split these simple bug fixes out into their own issue so they can get merged independently.
The error that appears when a cherry-pick action fails is worded poorly:
It may have already been cherry-pick, or a more recent commit may have updated some of its content.
I suggest we update this to the following so we don't have to rely on ruby's past-tense magic method to understand the word "cherry-pick":
"A #{action.to_s.dasherize} may have already been performed with this #{@commit.change_type_title}, or a more recent commit may have updated some of its content."