Fix last_value record in internal_ids for epics

What does this MR do?

Execution on database-lab https://gitlab.slack.com/archives/CLJMDRD8C/p1606912772402100

exec UPDATE internal_ids
SET last_value = epics_max_iids.maximum_iid
FROM (
	SELECT MAX(epics.iid) AS maximum_iid
		,epics.group_id AS epics_group_id
	FROM epics
	GROUP BY epics.group_id
	) epics_max_iids
WHERE internal_ids.last_value < epics_max_iids.maximum_iid
	AND namespace_id = epics_max_iids.epics_group_id
	AND internal_ids.usage = 4


The query has been executed. Duration: 221.000 ms (edited) 

re #288811 (closed)

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