Instead of redefining font-weights, we override the BS variables and add
one extra font-weight in the newly-introduced extended utilities file.
After this change all the variables needed replacing and some tweaking
was needed to get the same or closely similar result as before this
change.
By doing so the font-weight classes in the typography file were obsolete
and hence removed.
Some other font-weight issues which were already there have been fixed
in this commit too.
5534245b21