fix: change schema from obj to null

[pkdotson]

SUMMARY

This is a fix for a issue where a user changes database and the sql_json api would fail because it is expecting nullable string instead of object.

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 #19624 (a4ceb9d) into master (f91f83d) will decrease coverage by 0.12%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #19624      +/-   ##
==========================================
- Coverage   66.65%   66.52%   -0.13%     
==========================================
  Files        1680     1681       +1     
  Lines       64292    64308      +16     
  Branches     6564     6564              
==========================================
- Hits        42854    42783      -71     
- Misses      19736    19852     +116     
+ Partials     1702     1673      -29     

Flag	Coverage Δ
javascript	51.21% <ø> (-0.25%)	⬇️

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

Impacted Files	Coverage Δ
superset-frontend/src/SqlLab/actions/sqlLab.js	60.39% <ø> (ø)
...ts/nativeFilters/FilterBar/FilterControls/state.ts	0.00% <0.00%> (-75.00%)	⬇️
...veFilters/FilterBar/FilterControls/FilterValue.tsx	6.59% <0.00%> (-53.85%)	⬇️
...tend/src/filters/components/Time/transformProps.ts	0.00% <0.00%> (-50.00%)	⬇️
...oard/components/nativeFilters/FilterCard/index.tsx	10.00% <0.00%> (-50.00%)	⬇️
...d/src/filters/components/Time/TimeFilterPlugin.tsx	0.00% <0.00%> (-47.06%)	⬇️
...Filters/FilterBar/FilterControls/FilterControl.tsx	29.03% <0.00%> (-41.94%)	⬇️
...rset-frontend/src/filters/components/Time/index.ts	66.66% <0.00%> (-33.34%)	⬇️
...hboard/components/nativeFilters/FilterBar/utils.ts	53.84% <0.00%> (-23.08%)	⬇️
...ts/nativeFilters/FilterBar/ActionButtons/index.tsx	85.71% <0.00%> (-14.29%)	⬇️
... and 23 more

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[john-bodley]

@pkdotson thanks for the fix. Would you mind adding unit tests—or the bare minimum testing instructions—especially given the previous change resulted in a regression. We should strive to harden the robustness/quality of the product.

[pkdotson]

closing since ville fixed in #19664

[villebro]

Would you mind adding unit tests—or the bare minimum testing instructions—especially given the previous change resulted in a regression. We should strive to harden the robustness/quality of the product.

@pkdotson sorry for not having noticed this fix (I just needed to get it fixed for 1.5.0rc3). @john-bodley this would have been caught if the file was TypeScript. This is a good reminder of why we need to keep migrating those pesky .js* files to .ts*.