Don't leave an extra shell open on Linux/macOS

[danielzgtg]

exec can be used before a command to replace the shell process with the next command. It is commonly used at the end of scripts to save having to create a new process. This change should save a tiny bit of memory.

Before

home@daniel-desktop3:~$ ps -ef | grep Loader
home       24040   23833  0 18:18 ?        00:00:00 /bin/sh -c ./'Cities_Loader.sh' '--no-sandbox'
home       24041   24040  0 18:18 ?        00:00:00 /bin/sh ./Cities_Loader.sh --no-sandbox
home       24279   24231  0 18:18 pts/4    00:00:00 grep Loader

After

home@daniel-desktop3:~$ ps -ef | grep Loader
home       25315   25142  0 18:20 ?        00:00:00 /bin/sh -c ./'Cities_Loader.sh' '--no-sandbox'
home       25462   24231  0 18:20 pts/4    00:00:00 grep Loader