[8u] RFR 8242335: Additional Tests for RSASSA-PSS

[Aleksey Shipilev]

Original fix:
   https://bugs.openjdk.java.net/browse/JDK-8242335

Patch applies cleanly to 8u, but it puts the test at wrong locations. I moved them near the rest of 
the tests at test/sun/security/rsa/pss. (Not sure if such a move requires the RFR, but here you go).

8u webrev:
   https://cr.openjdk.java.net/~shade/8242335/webrev.8u.01/

Testing: new tests pass

-- 
Thanks,
-Aleksey