chore: Squash discussion model (part 1)

[gzurowski]

The following models were removed from the discussion app:

• Comment
• Reply
• Thread

This change squashes 58 discussion migrations into a single migration and removes the unneeded creation and subsequent removal of the above models.

The 58 redundant migrations will be removed in a subsequent PR that will be deployed AFTER this change has been rolled out across all environments.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 69.64286% with 136 lines in your changes missing coverage. Please review.

Project coverage is 72.44%. Comparing base (0ebf53a) to head (cee9256).

Files with missing lines	Patch %	Lines
src/discussion/views.py	57.30%	111 Missing :warning:
src/discussion/serializers.py	77.02%	17 Missing :warning:
src/discussion/models.py	90.54%	7 Missing :warning:
src/paper/paper_upload_tasks.py	0.00%	1 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2441      +/-   ##
==========================================
- Coverage   72.44%   72.44%   -0.01%     
==========================================
  Files         464      462       -2     
  Lines       25298    25276      -22     
==========================================
- Hits        18328    18310      -18     
+ Misses       6970     6966       -4     

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.

:rocket: New features to boost your workflow:

• :snowflake: Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[sonarqubecloud[bot]]

Quality Gate passed

Issues
11 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud