Add LeakTest for Nuclei CLI

[tarunKoyalwar]

Please describe your feature request:

• follow-up of feat: fix utils and add goroutine leak unit tests #5112
• add similar leak test for nuclei runner which handles execution of nuclei as cli
• this allows us to flag any goroutine leaks before they are merged

Anything Else

• we have already added this leak test for go sdk ( both SimpleNucleiExecuter and ThreadSafeExecuter) , so this can be referred while implementing