Bug 1805143 - Remove output kwarg before calling side by side r=perftest-reviewers,sparky

Differential Revision: https://phabricator.services.mozilla.com/D164437

python/mozperftest/mozperftest/runner.py

@@ -208,6 +208,8 @@ def run_tools(mach_cmd, kwargs):
         artifacts = _create_artifacts_dir(kwargs, SRC_ROOT)
     tempdir = tempfile.mkdtemp()
 
+    if kwargs.get("output"):
+        kwargs.pop("output")
     s = SideBySide(str(tempdir))
     s.run(**kwargs)