[Feature] Bootstrap 5 layout support

[mackrais]

Q	A
Bug fix?	no
New feature?	yes
BC breaks?	no
Deprecations?	no
Fixed tickets	...

I have read the CLA Document and I hereby sign the CLA

Added bootstrap 5 layout support and added docs how make custom form theme template.

Frontend Changes (jQuery)
Frontend Changes (JS)

[github-actions]

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I have read the CLA Document and I hereby sign the CLA

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