Prepare for 4.1.6 release #529

Job	Run time
CI test (make validate)	51s
Code coverage (codecov)	0s
Build moodle-plugin-ci.phar	46s
Integration tests (8.2, master)	6m 34s
Integration tests (8.2, MOODLE_402_STABLE)	7m 11s
Integration tests (8.1, MOODLE_401_STABLE)	7m 11s
Integration tests (8.0, MOODLE_400_STABLE)	6m 56s
Integration tests (8.0, MOODLE_311_STABLE)	6m 28s
Integration tests (7.4, MOODLE_310_STABLE)	7m 30s
Integration tests (7.4, MOODLE_39_STABLE)	6m 17s
Integration tests (7.4, MOODLE_38_STABLE)	7m 51s
Integration tests (PHAR) (8.2, master)	6m 10s
Integration tests (PHAR) (8.1, MOODLE_402_STABLE)	7m 19s
Integration tests (PHAR) (8.0, MOODLE_401_STABLE)	7m 34s
Integration tests (PHAR) (7.4, MOODLE_400_STABLE)	5m 52s
	1h 24m 30s

Provide feedback