govuk-lint: Fix Style/VariableName
govuk-lint: Fix Style/VariableName

Fix offence:
    Style/VariableName: Use snake_case for variable names.[1]

[1] https://github.com/bbatsov/ruby-style-guide#snake-case-symbols-methods-vars

alphagov/paas-cf,jimconner/paas-cf,alphagov/paas-cf,alphagov/paas-cf,alphagov/paas-cf,jimconner/paas-cf,jimconner/paas-cf,jimconner/paas-cf,jimconner/paas-cf,alphagov/paas-cf,jimconner/paas-cf,alphagov/paas-cf,alphagov/paas-cf,jimconner/paas-cf,alphagov/paas-cf