Model/scenario selectors can fail for CMIP6 indicators

[brucecrevensten]

STR:

• Go to CMIP6 Freeze/Thaw Indicator
• Pick Fairbanks
• Switch model to EC-Earth3-Veg. Look at the data.
• Switch scenario to SSP2-4.5.

Expected: either SSP2-4.5 isn't available or the data switches. Actual: doesn't switch, console error: TypeError: p[l.scenario][l.model][e] is null