Set @push early for EE
Set @push early for EE

In EE, there is need to call `merge_requests_for_source_branch`
before calling CE's `refresh_merge_requests,
in order to obtain the old diffs.

However that requires `@push`,
initialized inside CE's refresh_merge_requests.

However it can't be set early in EE, or static analysis would fail
because use of instance variables in module is discouraged.
So @push is set in execute instead.

iiet/iiet-git,dreampet/gitlab,iiet/iiet-git,dreampet/gitlab,axilleas/gitlabhq,stoplightio/gitlabhq,dreampet/gitlab,mmkassem/gitlabhq,iiet/iiet-git,stoplightio/gitlabhq,axilleas/gitlabhq,axilleas/gitlabhq,mmkassem/gitlabhq,iiet/iiet-git,stoplightio/gitlabhq,stoplightio/gitlabhq,mmkassem/gitlabhq,mmkassem/gitlabhq,axilleas/gitlabhq,dreampet/gitlab