Ignore SingleLineBlockParams Rubocop cop

This prevents us from choosing intention-revealing names for blocks
passed to `inject` and the like.

Change-Id: I6b95a184dfe086ff0f0604f75a7960ec68807a22
Reviewed-on: http://gerrit.causes.com/36707
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>