[test] ASSERT_OK instead of CHECK_OK when appropriate

Recently I ran a few tests in FIPS environment, and even if those were
expected to fail because our test scenarios use very short encryption
keys to run faster (compared with minimum allowed encryption key size
required by FIPS 140-2), I was unpleasantly surprised that some of those
simply crashed instead of exiting gracefully and reporting an error.

This patch addresses that for rpc-test and tls_socket-test.

Change-Id: I48d9bb2def2350c11afc41b9f08fa252c7ead65a
Reviewed-on: http://gerrit.cloudera.org:8080/19134
Reviewed-by: Attila Bukor <abukor@apache.org>
Tested-by: Kudu Jenkins
2 files changed