fix(world-map): remove categorical color control

[serenajiang]

SUMMARY

This PR reverts the changes in #19038 that affected world maps. #19038 added a control CATEGORICAL COLOR SCHEME to world maps which could override the linear color scheme if specified. This inadvertently broke all linear coloring for our world map charts because it was not possible to specify a null categorical color scheme.

Rather than fix the behavior of the categorical color scheme, I thought a better fix might be to just remove the categorical color scheme feature from world maps. World maps require the METRIC FOR COLOR control, so I'm not sure it makes sense to support a categorical color scheme.

TESTING INSTRUCTIONS

Make world map chart with linear color scheme, confirm colors applied as expected

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

@stephenLYZ @zhaoyongjie

[codecov]

Codecov Report

Merging #19781 (fd60f0a) into master (4ba62ca) will increase coverage by 0.00%.
The diff coverage is 0.00%.

@@           Coverage Diff           @@
##           master   #19781   +/-   ##
=======================================
  Coverage   66.34%   66.35%           
=======================================
  Files        1690     1690           
  Lines       64616    64611    -5     
  Branches     6656     6656           
=======================================
  Hits        42870    42870           
+ Misses      20045    20040    -5     
  Partials     1701     1701           

Flag	Coverage Δ
javascript	51.20% <0.00%> (+<0.01%)	⬆️

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

Impacted Files	Coverage Δ
...gins/legacy-plugin-chart-world-map/src/WorldMap.js	0.00% <0.00%> (ø)
.../legacy-plugin-chart-world-map/src/controlPanel.ts	100.00% <ø> (ø)
...egacy-plugin-chart-world-map/src/transformProps.js	0.00% <0.00%> (ø)
.../components/ExploreAdditionalActionsMenu/index.jsx	57.14% <0.00%> (ø)

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[zhaoyongjie]

LGTM. The color schema should show linear metrics value rather than categorical dimension values.

[stephenLYZ]

LGTM. I think categorical color usage scenario is when user wants to use the country column as color, so it makes some sense. Maybe we can add a new control to let user use color whether based on dimension or metric.