Code style: remove unneeded rubocop:disable comments
Code style: remove unneeded rubocop:disable comments

Fix the code style warning "Lint/UnneededDisable" found by
latest RuboCop, see:

http://www.rubydoc.info/gems/rubocop/RuboCop/Cop/Lint/UnneededDisable

Code style warning was:

test/shared/spec_helper.rb:57:41: W: Lint/UnneededDisable: Unnecessary disabling of Metrics/AbcSize.
                                        ^^^^^^^^^^^^^^^

Signed-off-by: Stephan Linz <0c883f969082385953c36ae90fd905b7f154694b@li-pro.net>

lipro-cookbooks/test-helper,rexut/lpn-cookbooks-test-helper,lipro-cookbooks/test-helper,rexut/lpn-cookbooks-test-helper