Is your feature request related to a problem? Please describe.
The current bibtex export crosswalk is only configured for single mode, not for list modes.

Describe the solution you'd like
We would like to have some multiple export format for bibtex as lists too.

Describe alternatives or workarounds you've considered

Additional context
Changing to SINGLE_AND_MULTIPLE shows sufficient results, cause the CSLItemDataProvider also has the method implemented
Single liner on configuration + additional tests