CmdLine does not forwarding signals

[EzzhevNikita]

Task name:
BashV3, CmdLineV2

Description:
Was added sending signals to the task child processes. (Need to trap SIGTERM signal in bash script)

Documentation changes required: (Y/N)
No
Added unit tests: (Y/N)
No
Attached related issue: (Y/N)
#11468
Checklist:

• Task version was bumped - please check instruction how to do it
• Checked that applied changes work as expected

[anatolybolshakov]

Please check if we need to apply changes for Powershell handler too

[anatolybolshakov]

LGTM, thanks!

[EzzhevNikita]

This problem is actual only for unix systems as Windows doesn't support POSIX signals and we can't send specific signals from Bash and CmdLine tasks on windows, so the the changes for powershell handler is unnecessary.

Please check if we need to apply changes for Powershell handler too

[alexander-smolyakov]

Could you please take a look at the comments? Other changes LGTM.

[EzzhevNikita]

@damccorm Could you please take a look this pr?