resources: Consolidate on the WikimediaUI “erroneous” color value

resources: Consolidate on the WikimediaUI “erroneous” color value

“Erroneous” color was updated to `#d33` in WikimediaUI color palette to
ensure WCAG 2.0 level AA conformance with both white and black.

Replacing all occurences of `#f00` and `#c00` to reflect color palette
change with the following caveats and exceptions:

- MW config styles are not amended, as it is out of scope and all
  boundaries and applications of WikimediaUI are yet to be defined;

- oldshared.css is excluded, as WikimediaUI isn't touching old skins; &

- errorbox with its current background is getting a lowered textual
  contrast but we still provide enough contrast for text size and bolded
  font, and this needs to be seen as intermediate standardization step.

Bug: T152025
Change-Id: Iba3362abaa1702599f0d68860f579aea2114801c