Error message on boxplots before clicking "Plot now"

[bnovotny]

Describe the bug If a point on the volcano plot is clicked before the "Plot Now!" button is activated, an error message appears in place of the boxplot.

To Reproduce Steps to reproduce the behavior:

1. Load data on "Ingest" tab
2. Go to "Playground" Tab
3. Go to "Diff Expr" Tab
4. Click on a point on the volcano plot

Expected behavior The boxplots should load, or there should be a message from validate() in the boxplot server such as "Hit 'plot now!' to load boxplots")

Screenshots

Desktop (please complete the following information):

• OS: Windows 10
• Browser: Chrome
• Version 0.0.9.2021-11-03

[ergonyc]

@ricoderks crushing bugs left and right!!👟🪳