Do not check flash button during calibration

It does not make sense to toggle night mode
or start another round of countdown during
calibration.

Closes #4.
1 job for dev/calibnightmode in 1 minute and 56 seconds (queued for 2 seconds)
Name Stage Failure
failed
job Build
========================= [FAILED] Took 36.40 seconds =========================

Environment Status Duration
------------- -------- ------------
esp8266 FAILED 00:00:47.173
esp32 FAILED 00:00:36.401
==================== 2 failed, 0 succeeded in 00:01:23.574 ====================
Cleaning up file based variables
ERROR: Job failed: exit code 1