Button "Return to group pages" should be "Return to group pages and collections"

[Kristina Hoeppner]

When we combined pages and collections, we updated the buttons in the personal, site and institution areas to say "Return to [site / institution] pages and collections". However, we didn't do that for groups. There it still says "Return to group pages".

To replicate:

1. Create a group.
2. Create a group page.
3. When you are on the "Edit" screen, there are buttons to return to other areas of Mahara.
Expected result: The bottom button says "Return to group pages and collections".
Actual result: It says "Return to group pages".

[Mahara Bot (dev-mahara)]

Patch for "master" branch: https://reviews.mahara.org/8871

[Steven (stevens-q)]

Manual Test Script:

1. Create a group.
2. Create a group page.
3. When you are on the "Edit" screen, there are buttons to return to other areas of Mahara.

Actual result: The bottom button says "Return to group pages and collections". ✔

Catalyst QA Approved ✔

[Mahara Bot (dev-mahara)]

Reviewed: https://reviews.mahara.org/8871
Committed: https://git.mahara.org/mahara/mahara/commit/c66006ba3bac801fd779f8d9d3902ca97b3bfc4a
Submitter: Robert Lyon (<email address hidden>)
Branch: master

commit c66006ba3bac801fd779f8d9d3902ca97b3bfc4a
Author: Maria Pappafloratos <email address hidden>
Date: Mon May 21 11:04:54 2018 +1200

Bug 1772327: Correct group button lang string

The button to return to group pages and collections
when editing a page required updating so that
it reads "Return to group pages and collections".

behatnotneeded

Change-Id: I3ae44e7bf3887517e93f52992e2290673e7f5da7