formatting: fix redundant parentheses stable

formatting: fix redundant parentheses

These were introduced by 0d055849d5f9d682ef931d2566b760d5c6bf7e52.

Differential Revision: https://phab.mercurial-scm.org/D10229

--- a/mercurial/dirstate.py	Fri Mar 12 20:19:12 2021 -0500
+++ b/mercurial/dirstate.py	Wed Mar 17 12:06:49 2021 +0100
@@ -1279,7 +1279,7 @@
                     or size == -2  # other parent
                     or fn in copymap
                 ):
-                    if (stat.S_ISLNK(st.st_mode) and size != st.st_size):
+                    if stat.S_ISLNK(st.st_mode) and size != st.st_size:
                         # issue6456: Size returned may be longer due to
                         # encryption on EXT-4 fscrypt, undecided.
                         ladd(fn)