tests: critical: fix naming and comments
tests: critical: fix naming and comments

We were referring to old function names and still using the task
terminology which can be confusing.

Signed-off-by: Anas Nashif <0d9952ec84ac43c159f6b7e7ed99a9080c00dd6e@intel.com>

zephyriot/zephyr,kraj/zephyr,kraj/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,GiulianoFranchetto/zephyr,mbolivar/zephyr,galak/zephyr,zephyriot/zephyr,explora26/zephyr,kraj/zephyr,Vudentz/zephyr,kraj/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,mbolivar/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,punitvara/zephyr,galak/zephyr,zephyriot/zephyr,ldts/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,explora26/zephyr,galak/zephyr,GiulianoFranchetto/zephyr,ldts/zephyr,nashif/zephyr,finikorg/zephyr,mbolivar/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,mbolivar/zephyr,finikorg/zephyr,ldts/zephyr,ldts/zephyr,punitvara/zephyr,Vudentz/zephyr,galak/zephyr,Vudentz/zephyr,mbolivar/zephyr,GiulianoFranchetto/zephyr,ldts/zephyr,explora26/zephyr,finikorg/zephyr,Vudentz/zephyr,zephyriot/zephyr,punitvara/zephyr,galak/zephyr,nashif/zephyr,punitvara/zephyr,GiulianoFranchetto/zephyr,zephyriot/zephyr,explora26/zephyr,GiulianoFranchetto/zephyr,explora26/zephyr,punitvara/zephyr,kraj/zephyr,finikorg/zephyr