Add support for charts to the extension API

Created by: felixfbecker

Adds support for charts in the extension API. It basically exposes a declarative, object literal API over recharts. I'm not 100% sure about all API aspects but am happy enough with this version to ship it for experimentation

Example usages:

• Line charts: https://github.com/sourcegraph/sourcegraph-search-insights
• Pie charts: https://github.com/codecov/sourcegraph-codecov/pull/52

Testing strategy: Storybooks.

Closes #10018

Created by: lguychard

@twop this would be interesting for you to review

Created by: codecov[bot]

Codecov Report

Merging #10550 into master will decrease coverage by 0.10%. The diff coverage is 22.05%.

@@            Coverage Diff             @@
##           master   #10550      +/-   ##
==========================================
- Coverage   44.64%   44.53%   -0.11%     
==========================================
  Files        1421     1424       +3     
  Lines       78502    78393     -109     
  Branches     6895     6861      -34     
==========================================
- Hits        35047    34916     -131     
- Misses      40182    40218      +36     
+ Partials     3273     3259      -14     

Flag	Coverage Δ
#go	47.70% <ø> (-0.08%)
#typescript	34.83% <22.05%> (-0.12%)
#unit	44.53% <22.05%> (-0.11%)

Impacted Files	Coverage Δ
web/src/views/niceTicks.ts	2.81% <2.81%> (ø)
web/src/views/ChartViewContent.tsx	30.61% <30.61%> (ø)
web/src/views/ViewContent.tsx	86.66% <66.66%> (-5.65%)
shared/src/components/linkClickHandler.ts	83.33% <83.33%> (ø)
shared/src/components/Markdown.tsx	100.00% <100.00%> (+12.50%)
enterprise/internal/campaigns/webhooks.go	33.90% <0.00%> (-8.78%)