Disable Fast-RTPS security tests until they work on Focal.

eProsima/Fast-DDS#1087 is the
issue that needs to be resolved.

Signed-off-by: Chris Lalancette <clalancette@openrobotics.org>

test_security/CMakeLists.txt

@@ -283,9 +283,12 @@ if(BUILD_TESTING)
     # TODO(mikaelarguedas) only Connext and FastRTPS support DDS-Security for now
     if(
       rmw_implementation STREQUAL "rmw_connext_cpp" OR
-      rmw_implementation STREQUAL "rmw_connext_dynamic_cpp" OR
-      rmw_implementation STREQUAL "rmw_fastrtps_cpp" OR
-      rmw_implementation STREQUAL "rmw_fastrtps_dynamic_cpp"
+      rmw_implementation STREQUAL "rmw_connext_dynamic_cpp"
+      # TODO(clalancette): As of 2020-04-09, Fast-RTPS doesn't support OpenSSL 1.1.1{d,e,f}.
+      # Since this is the version used in all of our target platforms, security tests can't work.
+      # Disable the tests until https://github.com/eProsima/Fast-RTPS/issues/1087 is resolved.
+      # rmw_implementation STREQUAL "rmw_fastrtps_cpp" OR
+      # rmw_implementation STREQUAL "rmw_fastrtps_dynamic_cpp"
     )
       custom_security_test_c(test_security_nodes_c
         "test/test_invalid_secure_node_creation_c.cpp")