Prevent overflowing static backdrop modal animation

TODO: backport the test too

* Move color utility callouts to start of page

Hierarchically/structurally, in the position they are currently at, the two callouts seem like they "belong" just to the "background color" section. Moving them to the start makes it clearer that those two callouts relate to everything in the page (both "Color" and "Background color" classes.

* Change heading level

otherwise the assistive technology callout looks like it's hierarchically under the "Dealing with specificity" heading

* docs(example): floating-labels' better Edge fallback

* docs(example): refactor floating-labels' CSS

Docs: add Gaël Poupard to the core team page

* Make example less broken-looking

don't want to give impression that now it's ok to just sprinkle `role="button"` around. this at least makes the `span` keyboard-focusable, similar to at least the start of a custom control

* remove .svg from shields.io badges since it's the default
* switch to shields.io for the OC badges too
* fix badgesize badges' labels

This requires git >= 2.10 but it was released almost 4 years ago.

Remove the class `.nav-item` from `.nav-link` inside the non `ul` or `ol` based navs.
This makes the consistency for `.nav-item` (This class will not be required on the `.nav-link`).
`.nav-item` was only required when you use `.nav-fill` or `.nav-justified` on the `.nav`. In other cases, it was redundant. And the purpose of `.nav-item` on `.nav-link`s can be achieved via flexbox utilities as well (Mentioned in the docs also).

* docs(example): drop IE workaround since it works fine in IE

* Serial comma

Co-authored-by: XhmikosR <xhmikosr@gmail.com>
Co-authored-by: Mark Otto <markd.otto@gmail.com>

fix(grid)[manual backport]: zero min-width on .col has too much side-effects

* instead of stopping event if onclick is triggered on input, call toggle method only if its not on checkbox inside a label

* add unit test

* add a dedicated test to ensure click event is forward to label

Co-authored-by: XhmikosR <xhmikosr@gmail.com>

Add role="dialog" in modals via JavaScript

Restore word-break: break-word on .text-break to fix text breaking on flex containers

Update to `@rollup/plugin-babel`

Allows use of background-color and more. Fixes #29033 for v5.

For some reason, custom checks in CSS columns need a new stacking order to maintain visibility. This PR adds `z-index: 1` to trigger that new stacking order. Since v5's forms are being redone entirely, and we're dropping IE10/11 there, I think this is totally fine to ship with v4 only. Will need to check v5's forms it in Edge though.

Fixes #29607

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Co-authored-by: XhmikosR <xhmikosr@gmail.com>

Co-authored-by: XhmikosR <xhmikosr@gmail.com>