Add pre wash redaction of any thing in the matrix

[brendanheywood]

ie if the matrix is going to set it to something specific in post wash, lets unset it ahead of time so there is no chance of it leaking. This also catches when a whole env is not configured yet but is refreshed too

This is still a cleaner in its own right and needs to be turned on. If a setting should be the same in an env as prod, then it needs to be explicit in the matrix rather than empty.