Unable to specify multiple values for a filter when querying the mail message store

See https://github.com/xwiki/xwiki-platform/commit/e085a165f03c56d859f4e21368850fe67d556833#commitcomment-23028197

One usecase is when trying to filter for error message statuses. A message can fail with one of 3 states so we can't write a query that filters the state field and give it all 3 possible values.

Workaround: use MailStatusResult.getAllErrors() that uses the state "%_error", thus using a partial match on the state field. However, this has limited reach outside the errors usecase.