return false when lack remote section

in config file.

Author: Im-Asher

Diff for: git/remote.py

@@ -621,6 +621,8 @@ def exists(self) -> bool:
             return True
         except cp.NoSectionError:
             return False
+        except ValueError:
+            return False
 
     @classmethod
     def iter_items(cls, repo: "Repo", *args: Any, **kwargs: Any) -> Iterator["Remote"]: