Dependency on local_accessibility_filescan

[mudrd8mz]

Given that the plugin is effectively useless without local_accessibility_filescan, would it make sense to declare it as a dependency?

Ref.: https://moodledev.io/docs/4.4/apis/commonfiles#versionphp

[devnoot]

Probably -- Thanks for opening the issue. Will close when the update drops, but if you're keen on issuing a PR I can merge it in.

[devnoot]

See branch 18-deps