Run mount from script to make initctl.sh kill/terminate work correctly with mount processes

[Aspirisha]

Before this change, we saved pid of piped grep instead of mounting process. Besides that, ./initctl.sh expects that pids saved in pids.txt to correspond to parents of actual processes that are required to be killed, so we add dedicated mount.sh script that will serve as such parent process, and we save its pid instead.

[github-actions[bot]]

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