shebang must be placed at the first line.

[fujiwara]

Hi!

I'm using zsh. Currently, the script seems to run by a /bin/sh, not by bash.
shebang must be placed at the first line.

$ echo $SHELL
/bin/zsh
$ ./check-ecs-exec.sh
./check-ecs-exec.sh: 10: set: Illegal option -o pipefail

After this patch applied, becomes to run as bash.

$ ./check-ecs-exec.sh 
Usage:
  ./check-ecs-exec.sh YOUR_ECS_CLUSTER_NAME YOUR_ECS_TASK_ID

[toricls]

You're absolutely right, thank you @fujiwara!