DEP Increase minimum version of silverstripe/framework #349

Job	Run time
CI / Context	1s
CI / Generate matrix	18s
CI / Check governance	0s
CI / 8.1 prf-low mysql57 phpunit all	1m 59s
CI / 8.2 mariadb phpunit all	2m 15s
CI / 8.3 mysql80 phpunit all	1m 50s
CI / 8.1 mysql57 phplinting	1m 29s
CI / 8.1 mysql57 phpunit all mfa	1m 34s
CI / 8.1 mysql57 phpunit all session-manager	1m 56s
CI / 8.1 mysql57	1m 41s
CI / Dispatch tag patch release	0s
	13m 3s

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