Fix usage of bare 'except'

flake8 reports:

  E722 do not use bare 'except'

Replace them with 'except Exception' per [1] which says:

  Bare except will catch exceptions you almost certainly don't want
  to catch, including KeyboardInterrupt (the user hitting Ctrl+C) and
  Python-raised errors like SystemExit

  If you don't have a specific exception you're expecting, at least
  except Exception, which is the base type for all "Regular" exceptions.

[1] https://stackoverflow.com/a/54948581

Change-Id: Ic555ea9482645899f5b04040ddb6b24eadbf9062
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/254606
Reviewed-by: Mike Frysinger <vapier@google.com>
Tested-by: David Pursehouse <dpursehouse@collab.net>

project.py

@@ -2619,7 +2619,7 @@ class Project(object):
                                                   (self.worktree)):
                 platform_utils.rmtree(platform_utils.realpath(self.worktree))
               return self._InitGitDir(mirror_git=mirror_git, force_sync=False)
-            except:
+            except Exception:
               raise e
           raise e
 
@@ -2864,7 +2864,7 @@ class Project(object):
         try:
           platform_utils.rmtree(dotgit)
           return self._InitWorkTree(force_sync=False, submodules=submodules)
-        except:
+        except Exception:
           raise e
       raise e