transaction: fix hg version check when loading journal

Differential Revision: https://phab.mercurial-scm.org/D1891

mercurial/transaction.py

@@ -612,7 +612,7 def rollback(opener, vfsmap, file, repor
         lines = fp.readlines()
         if lines:
             ver = lines[0][:-1]
-            if ver == str(version):
+            if ver == (b'%d' % version):
                 for line in lines[1:]:
                     if line:
                         # Shave off the trailing newline