Graphs are squashed with new redesign

[jaredlockhart]

The new redesign of Redash is very nice! But some graphs are getting squashed and are difficult to read now, example:

https://sql.telemetry.mozilla.org/dashboard/activity-stream-system-addon-experiment-57-release

I think it's because the X axis labels aren't being truncated so the graph is being smushed.

[washort]

Looks like the X axis on this visualization is set to "Category" scale - does it look right if you change it to "Datetime"?

[emtwo]

Yes, changing to "Datetime" resolves this particular issue. However I do still think it's a regression because the x-axis used to truncate before.

Though one thing to note is that specific x-axis datetime issues should be resolved/reduced with this PR: #365