Role fails to run in check mode

[Qwiz]

Hi!

I tried to run this role in check mode and got an error:

TASK [pdns_recursor-ansible : Set pdns version] ********************************************************************************************************************************************************************
fatal: [***]: FAILED! => {"msg": "The task includes an option with an undefined variable. The error was: 'dict object' has no attribute 'stdout'\n\nThe error appears to be in './roles/pdns_recursor-ansible/tasks/install-Linux.yml': line 40, column 7, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n\n    - name: Set pdns version\n      ^ here\n"}

This happens because task Obtain pdns version string doesn't run in check mode. So _pdns_rec_ver_output variable doesn't have a stdout key.

https://github.com/PowerDNS/pdns_recursor-ansible/blob/master/tasks/install-Linux.yml#L29
Fix is simple, just put check_mode: no in this task. Command doesn't change anything, so it is completely safe to run in even in check mode.