fix: compare remote branches

In the previous release (#34) we compared the remote destination. This works fine but we should compare both repos based on the remote. The pull request is created remote so the pull request description should reflect the remote state.

Issue: #32, #34

pull_request_codecommit/git/client.py

@@ -33,15 +33,19 @@ def current_branch(self) -> str:
         return self.__execute(["branch", "--show-current"])
 
     def get_commit_messages(self, destination_branch: str) -> Commits:
+        self.fetch()
         messages = self.__execute(
-            ["log", f"origin/{destination_branch}..{self.current_branch}"]
+            ["log", f"origin/{destination_branch}..origin/{self.current_branch}"]
         )
 
         return Commits(messages)
 
     def checkout(self, destination: str) -> None:
         self.__execute(["checkout", destination])
 
+    def fetch(self) -> None:
+        self.__execute(["fetch"])
+
     def pull(self) -> None:
         self.__execute(["pull"])