Git commits in Moodle 3.6.7 by Mikhail Golenkov

commit 84a8b1b2df104856c117183f3fa700aa2b15116b
Author: Mikhail Golenkov <mikhailgolenkov@catalyst-au.net>
Date:   Tue, 22 Oct 2019 06:43:15 +0800
Tag:    v3.6.7

MDL-66973 search: Reset Content writer after test.

commit 2d1b49b953ebd66d585719cd6f8dbc34c227d067
Author: Mikhail Golenkov <mikhailgolenkov@catalyst-au.net>
Date:   Mon, 07 Oct 2019 13:34:42 +0800
Tag:    v3.6.7

MDL-66864 upgrade: Delete non-mutual contacts in chunks.