Use multiple certs per s2n_config in s2n_self_talk_test.c
Use multiple certs per s2n_config in s2n_self_talk_test.c

To get some basic coverage in unit tests for multicert. A majority of
test coverage is in integration tests.

PKRoma/s2n,PKRoma/s2n,awslabs/s2n,alexeblee/s2n,wcs1only/s2n,awslabs/s2n,alexeblee/s2n,PKRoma/s2n,raycoll/s2n,raycoll/s2n,colmmacc/s2n,awslabs/s2n,awslabs/s2n,raycoll/s2n,PKRoma/s2n,alexeblee/s2n,raycoll/s2n,colmmacc/s2n,wcs1only/s2n,wcs1only/s2n,wcs1only/s2n,colmmacc/s2n,wcs1only/s2n,PKRoma/s2n,gibson-compsci/s2n,gibson-compsci/s2n,alexeblee/s2n,colmmacc/s2n,awslabs/s2n,wcs1only/s2n,raycoll/s2n,wcs1only/s2n,colmmacc/s2n,gibson-compsci/s2n,raycoll/s2n,gibson-compsci/s2n,alexeblee/s2n,PKRoma/s2n,gibson-compsci/s2n,alexeblee/s2n,PKRoma/s2n,gibson-compsci/s2n,colmmacc/s2n,awslabs/s2n,wcs1only/s2n,PKRoma/s2n