workflow: Back off stale bot a bit
workflow: Back off stale bot a bit

Change the stale bot to 180 days before initial flag.  In addition,
avoid issues entirely that have the 'someday' label applied.

Signed-off-by: David Brown <0af22db655f3ade5845314d695c1f4910314b0cb@linaro.org>

runtimeco/mcuboot,ATmobica/mcuboot,runtimeco/mcuboot,ATmobica/mcuboot,runtimeco/mcuboot,ATmobica/mcuboot,runtimeco/mcuboot,ATmobica/mcuboot,ATmobica/mcuboot,runtimeco/mcuboot