Correct WAF sales resource

Why is this change being made?

The current text is misleading. While the OWASP ModSecurity Core Rule Set doe cover the OWASP top 10, it's actually much more than that.

Does this MR meet the acceptance criteria?

Assign to DRI

• Did you assign this change to the correct DRI of the page or information you are changing?

Conformity

• Added description to this MR explaining the reasons for the proposed change, per say-why-not-just-what

/cc @whaber