Disable "New Realease"`s modal dismiss when clicked outside view

[gtroja]

USER CONTEXT:
I, as a developer trying to upload an app bundle, am accessing the /distribute/releases page.
When I click the new realease a right-side-modal is shown, which cover only part the previous screen.

Using that modal's upload section, I send a large file, usually 200Mb, and it takes a minute or two.
After the upload is done, in the next view of the modal there`s a text editing page.

THE PROBLEM:
sometimes text editing requires clicking and dragging sections of texts.
Sometimes the text is close to the edges of the modal.
sometimes I misclick outside the modal and the modal gets immediatly closed, discarting my file upload and texts.

SOLUTION:

• Add a confirmation alert
• disable the dismiss behaviour of clicking outside modal