Remove some upstreamed custom changes
Remove rPHAB8282af06e8948f7d3a9c197f10ea99b005e5c252 and remove rPHAB2d2788ef94c2d2c7bc0a034833879fed4722a463.
As we don't use an arcanist based workflow there won't be checks for the CSS changes. In case of conflicts, we need to run ./bin/celerity map
to update the CSS per https://we.phorge.it/book/contrib/article/adding_new_css_and_js/
Bug: T341799