Aligning anonymous settings dialog appearance with dialogs
elsewhere by
- setting base `font-size` to 14px to conform with Vector elsewhere –
size is not inherited to the dialog as it's a direct child of `body`
- increasing contrast on descriptive paragraphs to conform with
WCAG level AA
- reducing inner `padding`s slighty to conform with 8px grid
- aligning `border-color` and `box-shadow` values
- replacing static value with LESS variable
Also removing stylelintrc override rule which has been only around
for the old `box-shadow` value.
Bug: T178607
Change-Id: I738e0be11f3d1c94ea03288e0dddc1b983a6c729
