Fix pre-existing CodeQL warnings

- common.py get_git_branch: add explicit return when no branch found
- common.py is_same_pivot: add explicit return False for non-matching
- torch_ani.py write_input_file: match parent class signature

Author: alongd

arc/common.py

@@ -314,6 +314,7 @@ def get_git_branch(path: str | None = None) -> str:
         for branch_name in branch_list:
             if '*' in branch_name.decode():
                 return branch_name.decode()[2:]
+        return ''
     else:
         return ''
 
@@ -1365,6 +1366,7 @@ def is_same_pivot(torsion1: list | str,
         return False
     if torsion1[1:3] == torsion2[1:3] or torsion1[1:3] == torsion2[1:3][::-1]:
         return True
+    return False
 
 
 def is_same_sequence_sublist(child_list: list, parent_list: list) -> bool:

arc/job/adapters/torch_ani.py

@@ -179,7 +179,7 @@ def __init__(self,
                             xyz=xyz,
                             )
 
-    def write_input_file(self, settings: dict) -> None:
+    def write_input_file(self, settings: dict | None = None) -> None:
         """
         Write the input file to execute the job on the server.
         """