Update pgb-notify template

As part of #2628 (closed) databases.ini.erb was updated to use PgbouncerHelper. We need to update gitlab-ctl pgb-notify to use this as well.

This needs to be fixed before 9.5.1 goes out

/cc @marin

created branch 2703-update-pgb-notify-template

mentioned in merge request !1864 (closed)

I asked @jivanvl to revert !1858 (merged) from 9.5.1 as it would break PG HA. Once this is fixed, then both can be pulled in.

created branch 2703-update-pgb-notify-template

mentioned in merge request !1873 (merged)

mentioned in issue gitlab-com/infrastructure#2581

marked this issue as related to #2571

closed via merge request !1873 (merged)

closed via commit 4871a2bd

mentioned in commit 4871a2bd

mentioned in commit f8b8ec4d

mentioned in commit c3badf6a