Move CRNG test to providers

Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/11682)

diff --git a/crypto/rand/rand_crng_test.c b/providers/implementations/rands/rand_crng_test.c
similarity index 100%
rename from crypto/rand/rand_crng_test.c
rename to providers/implementations/rands/rand_crng_test.c