fix: nvd3 annotation tooltip

[etr2460]

🐛 Bug Fix

It looks like a long time ago, the sourceType field for annotations was migrated from being table to NATIVE. This broke the tooltip for annotations. Since I'm quite unfamiliar with this code, and for backwards compatibility, I've left the old selector in but also added the new one which should resolve the issue.

New class name in superset:

to: @ktmud @graceguo-supercat @kristw

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[codecov]

Codecov Report

Merging #540 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #540   +/-   ##
=======================================
  Coverage   23.21%   23.21%           
=======================================
  Files         291      291           
  Lines        6790     6790           
  Branches      675      675           
=======================================
  Hits         1576     1576           
  Misses       5176     5176           
  Partials       38       38           

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[etr2460]

After researching a bit more, it seems like the old class is still applied for annotation events built from a table as opposed to an annotation layer. Therefore, we need both classes here for the styles to apply properly