Fix long comment error on dashboard (#89002)
Fix dashboard comment failure due to the following trace:
```
Traceback (most recent call last):
File "/scratch/anijain/dashboard/work/pytorch/benchmarks/dynamo/runner.py", line 1180, in <module>
DashboardUpdater(args).update()
File "/scratch/anijain/dashboard/work/pytorch/benchmarks/dynamo/runner.py", line 1119, in update
self.comment_on_gh(comment)
File "/scratch/anijain/dashboard/work/pytorch/benchmarks/dynamo/runner.py", line 1096, in comment_on_gh
subprocess.check_call(
File "/scratch/anijain/dashboard/env/lib/python3.9/subprocess.py", line 368, in check_call
retcode = call(*popenargs, **kwargs)
File "/scratch/anijain/dashboard/env/lib/python3.9/subprocess.py", line 349, in call
with Popen(*popenargs, **kwargs) as p:
File "/scratch/anijain/dashboard/env/lib/python3.9/subprocess.py", line 951, in __init__
self._execute_child(args, executable, preexec_fn, close_fds,
File "/scratch/anijain/dashboard/env/lib/python3.9/subprocess.py", line 1821, in _execute_child
raise child_exception_type(errno_num, err_msg, err_filename)
OSError: [Errno 7] Argument list too long: '/data/home/anijain/miniconda/bin/gh'
srun: error: a100-st-p4d24xlarge-27: task 0: Exited with exit code 1
```
That is, we were trying to execute a gh command in the OS that was too long.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/89002
Approved by: https://github.com/davidberard98
