feat: Enable using flag -detailed-exitcode in action terraform plan

[mknapcok]

This adds functionality to use flag -detailed-exitcode in action terraform plan.

-detailed-exitcode  Return detailed exit codes when the command exits. This
                      will change the meaning of exit codes to:
                      0 - Succeeded, diff is empty (no changes)
                      1 - Errored
                      2 - Succeeded, there is a diff