Pipeline editor - Improve "cancel" button experience in commit form

Currently if you click on the cancel button in the commit form, it will reset the pipeline text editor content to the latest committed version. This is not what a user might expect since it's tied in to the commit form. In other sections, this cancel button is there to abort the commit, but since where the form is on the same page as you edit, it make no sense.

After a quick chat with @nadia_sotnikova, it seems we could repurpose the cancel button to be clear content. Clicking on it would open a modal asking you if you are sure that you want to return to your latest committed version, and then apply the changes.

The decision landed on:

• Rename the "cancel" button "Reset"
• Add a modal when clicking on reset to ask the user to confirm. Modal text: "Reset form to last committed version"
• Leave the button enabled for now.