Fix/remove support search routing to /search/cat/?forums=1

[jonoaldersonwp]

Searching on /support/ eventually deposits the user on /search/{{term}}/?forums=1.

I assume that the forums parameter is meant to filter the results to the forum, but it doesn't do so.

Could we either:

• Filter correctly
• Alter whatever process drops the user here to remove the ?forums=1 param

[dd32]

In 8210:

Support Forums: Drop the ?forums=1 parameter from the Support Forum search redirect as it's not used by /search/.

It seems support for ?forums= (and documentation, blogs, and bugs) was lost 8 years ago when we switched from Yahoo to Google search.

Fixes #4125.