Change the return link attached to "← All certificates" to take BuddyPress "My Certificate" page into account.

**Is your feature request related to a problem? Please describe.**
With BuddyPress and LifterLMS installed, when a user navigates to `/members//courses/my-certificates/`, clicks on a cerficate, and then clicks on "← All certificates", the page `dashboard/my-certificates/` is loaded instead of `/members//courses/my-certificates/`. You can [watch this video](https://share.getcloudapp.com/8LuqLYOx) (sent to the customer) to see what I mean.

**Describe the solution you'd like**
1. If a user navigates to `/members//courses/my-certificates/`, clicks on a cerficate, and then clicks on "← All certificates", the return link should be `/members//courses/my-certificates/`.
2. If a user navigates to `dashboard/my-certificates/`, clicks on a cerficate, and then clicks on "← All certificates", the return link should be `dashboard/my-certificates/`.
3. On the other hand, if the user manually types a link to a certificate (or clicks on a shareable certificate link), the return link when "← All certificates" is ambigous. Should it return to `/members//courses/my-certificates/` or should it return to `dashboard/my-certificates/`? The site administrator should have an option to choose what the appropriate return link should be when a certificate is manually typed or pasted in the browser's URL bar.

**Describe alternatives you've considered**
None.

**Side effects**
Fixing this for BuddyPress should also fix this for BuddyBoss, which is a fork of BuddyPress.

**Affected tickets**
Affected customers include HS-216423.

Start by tracing how the certificate page builds the “← All certificates” link for the BuddyPress path `/members//courses/my-certificates/` and the `dashboard/my-certificates/` path. Review how a certificate’s originating location could be retained, then clarify the administrator’s preferred fallback for directly opened or shared certificate links. Done means both navigation flows return to their originating page and the fallback is configurable.

Written by the indexing model from the issue text.