Fix array merge exception on return from get_user_events_all

[catalyst-marcus-green]

get_user_events_all returns a database record causing exception on array_merge. When functionname is get_user_events_all it returns an iterator rather than array which is typically a mysql or pgsql record type. This triggers the exception. This change populates the events array with instances of database record for iteration later on.
There may be a similar issue on
https://github.com/catalyst-marcus-green/moodle-local_assessfreq/blob/7a4959f62d9fec892d44dcd64d9f66f820c3d466/classes/frequency.php#L1299
But I will leave that to a later update.

Single button was throwing a deprecation error in the behat test and is only to do with ensuring the tests pass.

There are other unrelated behat failures that have not worked in quite a long time.

[catalyst-eu]

Ok, this changes looks good to me. As noted, there are a lot of failures from the CI checks, but these are existing fails, not introduced by this change.

[marxjohnson]

That was me who did the review, I forgot I was logged in from a different account. Merging.