Change yumrepo attribute 'name' to 'descr' to suppress yum warning

To suppress yum warning: 'Repository 'sensu' is missing name in
configuration, using id'

- **descr**
    A human-readable description of the repository.
    This corresponds to the name parameter in `yum.conf(5)`.
    Set this to `absent` to remove it from the file completely.  Valid
    values are `absent`.  Values can match `/.*/`.