Resolve "missing test case for OSBA with planar FOA/HOA input"

• Related issues: #930 (closed)
• Requested reviewers: @tyagiri @kiene

Reason why this change is needed

OSBA with planar SBA input is currently not tested in the CI pipeline

Description of the change

add a test case to self_test.prm

Affected operating points

codec itself is not affected

Related to #930 (closed)