Fixing a bug in redirect_back when query params would fail to match t…

[jwoertink]

Purpose

Fixes #1889

Description

There was a little inconsistency between previous_url and redirect_back that caused some issues. When request.resource is used, that will include any query params. So when you do a comparison between request.resource == referer_path this might look like if "/path?a=1" == "/path".

Checklist

• - An issue already exists detailing the issue/or feature request that this PR fixes
• - All specs are formatted with crystal tool format spec src
• - Inline documentation has been added and/or updated
• - Lucky builds on docker with ./script/setup
• - All builds and specs pass on docker with ./script/test