Image_metadata.tsv is too big

[gwaybio]

In a recent dataset, the image_metadata.tsv was >300MB which is larger than the allowed file size for github. We should do two things:

• Compress this to a .tsv.gz file
  • Fix here: https://github.com/broadinstitute/pooled-cell-painting-profiling-template/blob/b51400588563e61a90cccd20e2a7b2a2f7c4bea2/config/utils/config_utils.py#L147
• Automatically add it to a new .gitattributes file to enable tracking via git lfs

[gwaybio]

also note that the file complete_perturbation_count_per_site.tsv.gz is too large.

If we track all .gz files then bullet point 2 will solve this file as well.