add batch_size arg, time different steps

[teovin]

• Add the optional batch-size flag to invoke command. If not passed, it will default to 1000. This is so that we can run the job without a guids CSV or a single WARC guid. Now we can run the job with docker compose exec web invoke dev.benchmark-wacz-conversion --benchmark-log='perma/wacz_experiment/benchmark.csv' or docker compose exec web invoke dev.benchmark-wacz-conversion --benchmark-log='perma/wacz_experiment/benchmark.csv' --batch-size=500
• Time the different steps of the conversion for granularity.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 0% with 19 lines in your changes are missing coverage. Please review.

Project coverage is 70.27%. Comparing base (c1eaead) to head (d32d3bd). Report is 30 commits behind head on develop.

:exclamation: Current head d32d3bd differs from pull request most recent head aebd55d. Consider uploading reports for the commit aebd55d to get more accurate results

Files	Patch %	Lines
perma_web/perma/celery_tasks.py	0.00%	13 Missing :warning:
perma_web/tasks/dev.py	0.00%	6 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #3505 +/- ## =========================================== - Coverage 70.35% 70.27% -0.08% =========================================== Files 48 48 Lines 6611 6627 +16 =========================================== + Hits 4651 4657 +6 - Misses 1960 1970 +10 ```

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[teovin]

Looks great! I just have one performance-related suggestion 🙂. Really looking forward to running this experiment!!

Thank you for the great explanation and the change is pushed! :)