MM-31064: Simplify indentation (#16565)

* MM-31064: Simplify indentation

Reduce indentation where possible.

```release-note
NONE
```

Command ran to verify:
golangci-lint run --disable-all --enable golint --max-issues-per-linter=10000 --max-same-issues=100000 ./... | grep "block ends with a return state"

https://mattermost.atlassian.net/browse/MM-31064

* incorporate review comments

* enable golint for outdent rule

* fix remaining issues

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

store/sqlstore/user_store.go

@@ -518,9 +518,8 @@ func applyMultiRoleFilters(query sq.SelectBuilder, systemRoles []string, teamRol
 
 	if len(sqOr) > 0 {
 		return query.Where(sqOr)
-	} else {
-		return query
 	}
+	return query
 }
 
 func applyChannelGroupConstrainedFilter(query sq.SelectBuilder, channelId string) sq.SelectBuilder {