Fails silently if 'curl' is not available

[kpfleming]

I know I've got a weird configuration here, but I'm using my own container image with Actions, and the image did not include curl.

I added reviewdog/action-setup@v1 to one of my workflows, but using reviewdog later in the workflow failed.

When I inspected the logs, the installation had failed since curl was not available, and then the execution of reviewdog -h also failed since it didn't get installed, but neither of those caused the action to fail and the workflow continued.