fix command line run for refinforce_learn_qnet in pl_examples

[sidhantls]

What does this PR do?

Unused default arguments in argparse were removed from refinforce_learn_qnet.py that was causing an error through command line. Previously, it was adding model specific args, warm_start_size and max_episode_reward, both of which the model doesn't take inputs to. I also pass add_helper=False to ArgumentParser because of the conflicting help options error (issue 5382).

warm_start_size and warm_start_steps both mean the same thing, but only warm_start_steps is used in the model so we can remove warm_start_size argument. Same as in its implementation in pl_bolts

Fixes #5381, #5382 (duplicate)

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[codecov]

Codecov Report

Merging #5414 (35a3afc) into master (18d2ae8) will not change coverage.
The diff coverage is n/a.

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  Hits         9339    9339           
  Misses        666     666           

[Borda]

good catch

[sidhantls]

@Borda Sure :)

Unrelated to this pr- this example does not allow command line arguments for Trainer as most of the other examples do. Can only pass model specific args. If you think this is will be useful lmk, will submit a pr for it

[tchaton]

Why did you set add_help=False ? It is always better to enable help.

[sidhantls]

The code doesn't run with add_help=True ( #5382)

Since we supply our own help text for each argument, I think we can set this as False. With set to False, running python pl_examples\domain_templates\reinforce_learn_Qnet.py --help still displays the custom help options we provided.

[sidhantls]

edit: here add_help=False is in the parent parser, but for the parser adding model specific args add_help=True by default. When it's set to True on both parsers, this conflicting option error occurs so one of them can be set to False

pls re-review