Right now our tests expect SCOSSL vs OSSL-default behaviors by "am I Azure Linux 3". But it's possible to run AzL3 without SCOSSL, so the tests fail when they don't see the expected behavioral changes.

In discussion with SCOSSL people, they initially suggested checking if the SymCrypt-OpenSSL package was installed or not. Rather than link our tests up to a distro package manager, the next suggested alternative was to base the expectation on the presence of /usr/lib/ossl-modules/symcryptprovider.so.

It seems like a reasonable thing to do... the net effect being that we stop asking "Am I AzL3" and check a helper for "SCOSSL?", and that helper could be AzL3 && File.Exists("/usr/lib/ossl-modules/symcryptprovider.so").