remove: avoid a bogus warning about no tracked files when removing '.'

Previously, any files relative to the root of the repo that match the -I
patterns would be deleted, but the command exited with 1 after printing a
warning:

   $ hg remove -S -I 're:.*.txt' .
   removing sub1/sub2/folder/test.txt
   removing sub1/sub2/test.txt
   not removing .: no tracked files

mercurial/cmdutil.py

@@ -2088,7 +2088,7 b' def remove(ui, repo, m, prefix, after, f'
                     return True
             return False
 
-        if f in repo.dirstate or f in wctx.dirs() or insubrepo():
+        if f in repo.dirstate or f in wctx.dirs() or f == '.' or insubrepo():
             continue
 
         if os.path.exists(m.rel(join(f))):

tests/test-subrepo-deep-nested-change.t

@@ -113,7 +113,7 b' Check that deep archiving works'
 
 .. but first take a detour through some deep removal testing
 
-  $ hg remove -S -I 're:.*.txt' sub1
+  $ hg remove -S -I 're:.*.txt' .
   removing sub1/sub2/folder/test.txt (glob)
   removing sub1/sub2/test.txt (glob)
   $ hg status -S