Fix setKioskMode()

[intermittentnrg]

Fixes Uncaught TypeError: document.querySelector(...) is null

Reproducible in standalone browser

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.58%. Comparing base (36b61a2) to head (cb11e58).
Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #53   +/-   ##
=======================================
  Coverage   89.58%   89.58%           
=======================================
  Files           3        3           
  Lines         192      192           
=======================================
  Hits          172      172           
  Misses         20       20           

Flag	Coverage Δ
unittests	89.58% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[intermittentnrg]

Alternatively set query = "?kiosk" in core.py and remove grafana-studio.js setKioskMode()

I'd prefer this.

[amotl]

I don't have any objections about the alternative GH-54. What do you think, @maurerle?

[intermittentnrg]

I think we can close this PR in favor of #54 then.

[maurerle]

yes, that's not a proper fix anyway.

Checking if document.querySelector('[title="Enable kiosk mode"]') is null should be better