remove obsolete comment

Co-authored-by: Matt Drozt <[email protected]>

smartsim/_core/launcher/step/slurm_step.py

@@ -221,7 +221,7 @@ def _make_mpmd(self) -> t.List[str]:
         cmd = exe + args
 
         compound_env_vars = []
-        for mpmd_rs in self._get_mpmd():  # returns a list of runsettings
+        for mpmd_rs in self._get_mpmd():
             cmd += [" : "]
             cmd += mpmd_rs.format_run_args()
             cmd += ["--job-name", self.name]