ssl: remove special case of web.cacerts=! from remoteui()

It was introduced by b76d8c641746, which is no longer necessary thanks to
recent refactoring of sslutil including ef316c653b7f.

mercurial/hg.py

@@ -927,9 +927,7 b' def remoteui(src, opts):'
         for key, val in src.configitems(sect):
             dst.setconfig(sect, key, val, 'copied')
     v = src.config('web', 'cacerts')
-    if v == '!':
-        dst.setconfig('web', 'cacerts', v, 'copied')
-    elif v:
+    if v:
         dst.setconfig('web', 'cacerts', util.expandpath(v), 'copied')
 
     return dst