fix(dev.py): fix merge_pull_request output variable bug

gitea/dev.py

@@ -1,9 +1,9 @@
-    def _get_branch(self, branch: Optional[str], __user__: dict = None) -> str:
-        """Get effective branch with priority resolution."""
-        if branch:
-            return branch
-        if __user__ and "valves" in __user__:
-            user_valves = __user__.get("valves") if __user__ else None
-            if self.valves.ALLOW_USER_OVERRIDES and user_valves.USER_DEFAULT_BRANCH:
-                return user_valves.USER_DEFAULT_BRANCH
-        return self.valves.DEFAULT_BRANCH
+            if merged:
+                output = f"**PR #{pr_number} Merged Successfully**\n\n"
+                output += f"**Strategy:** {merge_strategy.upper()}\n"
+                if commit_sha:
+                    output += f"**Merge Commit:** `{commit_sha}`\n"
+                output += f"\n✅ The pull request has been merged into {owner}/{repo_name}."
+                return output
+            else:
+                return f"**PR #{pr_number} Merge Result:**\n\n{result}\n"