* processes any pending records which are not migrated yet
* bumps import_export version because of new commits_count attribute
* removes commits_count fallback method

There are several quick actions now that don't need this access - /todo and
/unsubscribe for instance - but when these were first added, there
weren't. Quick actions are now responsible for checking their own permissions.

Rinku 2.0.0 (the version we use) will remove the last character of a link if
it's a closing part of a punctuation pair (different types of parentheses and
quotes), unless both of the below are true:

1. The matching pair has different start and end characters.
2. There are equal numbers of both in the matched string (they don't have to be
   balanced).

Because epic index page includes also epics from subgroups
it's necessary to also get descendant group labels for filtering.
https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/4773#note_61236542

In some situations (listing labels for epics) we want to
list only group ancestor labels, this is already supported
in LabelsFinder we just need to enable additional parameters.

Also `set_issuables_index` method now loads project labels only if
@project is set (which is not used for epic group labels).

Closes gitaly#1046