Improve output of vale substitution rule

What does this MR do?

As raised in the linked issue, the message for since is not clear, as the suggestion could be because, or it could be after, depending on the usage of since.

As an MVC/POC, I've changed the message so that it outputs both because and after as possible solutions. As a result, the double quotes have to be moved from the message text, to the individual rule lines, but it seems to work properly:

• 
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Related issues

Resolves #273619 (closed)

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