feat: css template add/edit modal

[lilykuang]

SUMMARY

• css template add/edit modal

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

https://www.loom.com/share/8d206d73074d4c5bbf804d2e60924b29

TEST PLAN

• jest test

ADDITIONAL INFORMATION

• Has associated issue:
• [] Changes UI
• Requires DB Migration.
• Confirm DB Migration upgrade and downgrade tested.
• Introduces new feature or API
• Removes existing feature or API

[codecov-io]

Codecov Report

Merging #11296 into master will decrease coverage by 0.00%.
The diff coverage is 68.69%.

@@            Coverage Diff             @@
##           master   #11296      +/-   ##
==========================================
- Coverage   65.69%   65.68%   -0.01%     
==========================================
  Files         835      836       +1     
  Lines       39659    39771     +112     
  Branches     3610     3647      +37     
==========================================
+ Hits        26052    26122      +70     
- Misses      13498    13540      +42     
  Partials      109      109              

Flag	Coverage Δ
#cypress	55.58% <4.90%> (-0.39%)	⬇️
#javascript	62.77% <68.69%> (+0.05%)	⬆️
#python	60.87% <ø> (-0.03%)	⬇️

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

Impacted Files	Coverage Δ
...d/src/views/CRUD/csstemplates/CssTemplatesList.tsx	80.39% <47.05%> (-16.91%)	⬇️
...d/src/views/CRUD/csstemplates/CssTemplateModal.tsx	72.44% <72.44%> (ø)
superset/db_engine_specs/sqlite.py	65.62% <0.00%> (-9.38%)	⬇️
superset/utils/celery.py	82.14% <0.00%> (-3.58%)	⬇️
superset/result_set.py	96.69% <0.00%> (-1.66%)	⬇️
...set-frontend/src/dashboard/util/getDropPosition.js	90.47% <0.00%> (-1.59%)	⬇️
superset-frontend/src/SqlLab/actions/sqlLab.js	64.52% <0.00%> (-0.43%)	⬇️
superset-frontend/src/SqlLab/reducers/sqlLab.js	41.25% <0.00%> (-0.42%)	⬇️
superset-frontend/src/views/CRUD/hooks.ts	78.65% <0.00%> (+2.24%)	⬆️
... and 2 more

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[rusackas]

FWIW, we can do some fun stuff with this, e.g. width={"calc(100% - 100px)"} if you ever feel like it :D

If/when there are a lot of these modals kicking around, we should probably add a limited number of preferred values to the Theme or a constants file.

[rusackas]

Might not be worth the battle, but I'm curious if we could make the modal take up as much room on the screen as it can, and use a flexbox layout within the modal, which would let THIS component take up as much of the layout as possible, rather than limiting its height with a static value.

[nytai]

lgtm!