2185: Update reverse.rst r=mergify[bot] a=audioscavenger
updated the external proxy location pattern and added a note: do not add a ``/`` at the end
## What type of PR?
documentation
## What does this PR do?
### Related issue(s)
- did not bother to create an issue
## Prerequisites
Before we can consider review and merge, please make sure the following list is done and checked.
If an entry in not applicable, you can check it or remove it from the list.
- [ ] i would like to add [changelog](https://mailu.io/master/contributors/workflow.html#changelog) entry file but i don't know how
Co-authored-by: Eric <dev@derewonko.com>
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