Update outdated libraries in starter templates

[wenz]

Is your feature request related to a problem? Please describe.

The starter templates use outdated versions of some libraries, Bootstrap and jQuery.validate. These should be updated to the latest versions.

Describe the solution you'd like

Update the following libraries:

• jquery-validation (1.17.0 -> 1.19.1)
• Bootstrap (4.3.1 -> 4.4.1)

Additional context

I am excluding jQuery from that list, since the version currently used (3.3.1) has a security vulnerability, so upgrading it isn't just a feature request; also, there is a separate issue #20001 for it.

[mkArtakMSFT]

This is a dupe of #20001

[wenz]

I respectfully disagree. #20001 is about an insecure, old version of jQuery being used; this here is about non-insecure, outdated versions of other JavaScript libraries being used. I'd recommend to keep them separate, since #20001 is IMVHO more critical than this one here.