Make whitehall media requests spec more realistic
Make whitehall media requests spec more realistic

Currently the feature flag is set to 100 in all environments [1], and so
this makes the spec more realistic.

[1]:
https://github.com/alphagov/govuk-puppet/blob/476d9e764b42348deb8a2253be78d460d44c33c0/hieradata/common.yaml#L524

alphagov/asset-manager,alphagov/asset-manager,alphagov/asset-manager