fix: stop endless loading when dataset no longer exist

[pkdotson]

SUMMARY

This pr stops the endless loading in the dashboards when a dataset no longer exists and returns proper error info to the user.

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

before

Screen.Recording.2021-08-30.at.10.19.09.AM.mov

after

Screen.Recording.2021-08-30.at.10.21.47.AM.mov

TESTING INSTRUCTIONS

Delete a dataset that has associated chart in a a dashboard.
Go to the dashboard and ensure that the charts do no endlessly load.

ADDITIONAL INFORMATION

• [x ] Has associated issue: Fixes [dashboard] chart reload forever if delete attached dataset #16431
• 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 #16511 (05f6565) into master (62d8ab7) will decrease coverage by 0.00%.
The diff coverage is 20.00%.

@@            Coverage Diff             @@
##           master   #16511      +/-   ##
==========================================
- Coverage   76.63%   76.63%   -0.01%     
==========================================
  Files        1002     1002              
  Lines       53680    53684       +4     
  Branches     6852     6855       +3     
==========================================
+ Hits        41138    41139       +1     
- Misses      12305    12308       +3     
  Partials      237      237              

Flag	Coverage Δ
javascript	71.01% <20.00%> (-0.01%)	⬇️

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

Impacted Files	Coverage Δ
superset-frontend/src/chart/Chart.jsx	43.33% <20.00%> (-1.31%)	⬇️

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[ktmud]

Thanks for the fix!

[pkdotson]

/testenv up

[github-actions]

@pkdotson Ephemeral environment spinning up at http://54.212.36.232:8080. Credentials are admin/admin. Please allow several minutes for bootstrapping and startup.

[rusackas]

Thanks for the fix! Code LGTM.

It might at some point be worth considering a UX enhancement to this, where we surface the error more explicitly (as opposed to an "Unexpected Error" that you have to click), or potentially pop a page-level error (rather than only chart-level errors) to alert users to the problem. This is a heck of an improvement, though!

[github-actions]

Ephemeral environment shutdown and build artifacts deleted.