Remove the fixed height set on the card elements present in angular.io,
allowing the cards to have a dynamic height derived from their content
and thus removing overflow issues related to the browser's font-size,
make other minor css related adjustments to allow the card to look good
on the different browser's font-size settings
PR Close#42533
Cleans up AIO's Sass files by:
* Switching them all over to the `@use`-based API from Angular Material.
* Removing the import of the Material theming API in a bunch of places that weren't using it.
* Migrating the new usages of Sass utility functions to the new syntax (e.g. `map.get` vs `map-get`).
* Fixing a few files that were using 4 spaces for indentation instead of 2.
PR Close#42442
