Fix timeout -k implementation error

[nicksvv]

Hey @six2dez, that an error in timeout -k implentation, so right now Amass not working in some functions.

The timeout -k option takes two arguments:

1. The first argument (DURATION_KILL) is the duration after which the timeout command should send a KILL signal to the process if it's still running after the initial timeout period has elapsed. This duration should be specified in the same format as the DURATION argument (e.g., '15s' for 15 seconds, '1m' for 1 minute, '2h' for 2 hours, '3d' for 3 days, etc.).
2. The second argument is the initial timeout duration (DURATION) after which a TERM signal is sent to the process. The DURATION argument should be followed by the command to run and limit the execution time of.

So in the command timeout -k 1m ${AMASS_INTEL_TIMEOUT}m amass intel -d ${domain} -whois a TERM signal will be sent to the process after 15 minutes of execution. If the process continues to run 1 minute beyond this, a KILL signal will be dispatched to forcefully terminate it.

[six2dez]

Very well spotted! I don't know what I was thinking when I code that. Thanks a lot for contributing! Btw, I changed the branch to dev in order to follow the development process. Thanks again!