[Bugfix] Defer tooltip script loading until after HTML is parsed

[brett0000FF]

What does this PR do? What is the motivation?

• The tooltip functionality wasn't initializing on first page load in Chrome.
• After refreshing the page, it works as expected.
• This only started happening recently in Chrome.
• Added defer to script initialization in footer-scripts.html to make sure the HTML is parsed before the script runs.

Test instructions

1. Go to a page using a tooltip.
2. Make sure it displays on hover immediately.

Merge instructions

Merge readiness:

• Ready for merge

Merge queue is enabled in this repo. To have it automatically merged after it receives the required reviews, create the PR (from a branch that follows the <yourname>/description naming convention) and then add the following PR comment:

/merge

Additional notes