refactor: consistent migration tests organization

[ktmud]

SUMMARY

Small house-keeping to organize integration tests for migrations in a consistent manner.

1. Use full migration name in filenames
2. Use "__tests" as suffix to make filenames easier to read
3. Move one test from integration_tests/migration_tests to a new file following above convention

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

TESTING INSTRUCTIONS

ADDITIONAL INFORMATION

• Has associated issue:
• Required feature flags:
• Changes UI
• Includes DB Migration (follow approval process in SIP-59)
  • Migration is atomic, supports rollback & is backwards-compatible
  • Confirm DB migration upgrade and downgrade tested
  • Runtime estimates and downtime expectations provided
• Introduces new feature or API
• Removes existing feature or API

[codecov]

Codecov Report

Merging #19635 (029193b) into master (9a9e3b6) will decrease coverage by 12.83%.
The diff coverage is n/a.

❗ Current head 029193b differs from pull request most recent head c497e6f. Consider uploading reports for the commit c497e6f to get more accurate results

@@             Coverage Diff             @@
##           master   #19635       +/-   ##
===========================================
- Coverage   66.49%   53.65%   -12.84%     
===========================================
  Files        1681     1681               
  Lines       64370    64370               
  Branches     6583     6583               
===========================================
- Hits        42803    34538     -8265     
- Misses      19886    28151     +8265     
  Partials     1681     1681               

Flag	Coverage Δ
hive	?
mysql	?
postgres	?
presto	52.51% <ø> (ø)
python	56.23% <ø> (-26.15%)	⬇️
sqlite	?
unit	47.71% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
superset/utils/dashboard_import_export.py	0.00% <0.00%> (-100.00%)	⬇️
superset/key_value/commands/upsert.py	0.00% <0.00%> (-89.59%)	⬇️
superset/key_value/commands/update.py	0.00% <0.00%> (-89.37%)	⬇️
superset/key_value/commands/delete.py	0.00% <0.00%> (-85.30%)	⬇️
superset/db_engines/hive.py	0.00% <0.00%> (-85.19%)	⬇️
superset/key_value/commands/delete_expired.py	0.00% <0.00%> (-80.77%)	⬇️
superset/dashboards/commands/importers/v0.py	14.79% <0.00%> (-75.15%)	⬇️
superset/datasets/commands/importers/v0.py	24.82% <0.00%> (-68.80%)	⬇️
superset/databases/commands/test_connection.py	31.42% <0.00%> (-68.58%)	⬇️
superset/datasets/commands/update.py	25.88% <0.00%> (-68.24%)	⬇️
... and 265 more

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[zhaoyongjie]

LGTM! Thanks for the cleanup.