fix(modal): add primary button loading state to modals

[kgopal492]

SUMMARY

• Rationale: Saving a resource is not always instantaneous. In the AddDatasetModal, while a dataset is being saved, the primary "Add" button is not disabled - allowing user to click on the "Add" button multiple times while the resource is being saved. This allows the user to add duplicate datasets
• This PR adds a primaryButtonLoading prop to the Modal component
• The AddDatasetModal passes a loading prop to the Modal component while the resource creation is loading

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

Screen.Recording.2022-05-10.at.12.53.15.PM.mov

TESTING INSTRUCTIONS

• Add delay to superset.datasets.api.py in the POST function on the \ path (dataset creation path)
• Add a new dataset and verify that the button is disabled & loading while the dataset is being created

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

[rusackas]

@jess-dillard pinging for any design feedback you see fit.

[ghost]

@rusackas Looks good to me!

[eschutho]

This is great, thank you!

[codecov]

Codecov Report

Merging #20018 (3770e6f) into master (1f0daa9) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master   #20018   +/-   ##
=======================================
  Coverage   66.29%   66.29%           
=======================================
  Files        1712     1712           
  Lines       63974    63975    +1     
  Branches     6731     6732    +1     
=======================================
+ Hits        42410    42411    +1     
  Misses      19853    19853           
  Partials     1711     1711           

Flag	Coverage Δ
javascript	51.27% <100.00%> (+<0.01%)	⬆️

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

Impacted Files	Coverage Δ
superset-frontend/src/components/Modal/Modal.tsx	86.15% <100.00%> (+0.21%)	⬆️
...nd/src/views/CRUD/data/dataset/AddDatasetModal.tsx	41.66% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 1f0daa9...3770e6f. Read the comment docs.