Install NVM step needs pipefail

[pearj]

Describe the bug
If the wget command fails for any reasons during the "Install NVM" the error is ignored, and then the check nvm version step fails later.

Expected behaviour
The "Install NVM" command should fail when the wget command fails instead of ignoring it

To Reproduce
Use bad proxy environment settings and wget will fail with return code 8.

Shell
Bash

Desktop (please complete the following information):

• OS: RHEL 7.4
• Ansible Version 2.9.10

Additional context
For bash this should be fixable by setting pipefail. Eg: https://blog.christophersmart.com/2019/09/28/using-pipefail-with-shell-module-in-ansible/

[morgangraphics]

I've been doing quite a lot of work surrounding idempotency with this role. Thanks for pointing this out, I'll make it part of the work I am currently doing.