Make ctverif build optional until remote dep is up
Make ctverif build optional until remote dep is up

https://github.com/awslabs/s2n/pull/615 will track resolution.

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