[5.x] Fix enter key not submitting confirmation modal sometimes

[duncanmcclean]

This pull request adds a keybinding to the "enter" key when editing a section in a blueprint or fieldset.

This PR doesn't do it for tabs - I need to come back to them since I couldn't seem to get them working the same way. 🤔

Closes #10702.

[jackmcdade]

Hmm, this doesn't seem to work for me. 🤔 Tried Chrome and Safari and still the same behavior.

[duncanmcclean]

Oh, that's a pain. I'll take a look next week.

[jasonvarga]

Funny. We made it do this on purpose: #10537

[jasonvarga]

I pushed up fixes.

This is what was happening:

• When you're in a modal with a text field, hitting enter would "submit" the form.
• I say "submit" because it seems to just "click" the first submit button, which is Cancel. So the modal would just close.
• Buttons without a type attribute default to type="submit". The cancel button didn't have a type, so it was considered a submit button. It was missing type="button" which makes the button natively do nothing so you can add JS to it.

Now when you press enter, the first submit button (which is now "Submit") will be clicked and the modal form will submit and close as expected. 😅