[QA] Fix add file template tests

What does this MR do?

Both tests (Web IDE and non-Web IDE) needed some more waits.

The Web IDE test needed to wait for the new file modal to stop animating before clicking a button and it needed to wait for the modal to fade away before clicking another button. It also needed to click the commit button one more time (this seems to have been a change in the UI since it used to work without it before).

The non-Web IDE test needed to wait for loading to complete after committing a file.

Closes https://gitlab.com/gitlab-org/quality/nightly/issues/97 Closes gitlab-org/quality/staging#46 (closed)

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content