[Test] Enable back 5 tests failing with ethreads=1 after bugs fixed

[hukoyu]

5 tests are failing in sgx-lkl nightly build with SGXLKL_ETHREADS=1 ( 3 java, 1 dotnet, 1 ml/openvino) We are disabling them with PR https://github.com/lsds/sgx-lkl/pull/801

https://github.com/lsds/sgx-lkl/issues/415 (ml/openvino) https://github.com/lsds/sgx-lkl/issues/795 (java, helloworld) https://github.com/lsds/sgx-lkl/issues/796 (java, read_file, thread) https://github.com/lsds/sgx-lkl/issues/797 (dotnet)

We are skipping (disabling) these 5 tests for ETHREADS=1. They will continue to run for ETHREADS > 1 ( 4 and 8) We will enable these 5 tests after underlying bugs fixed.

[hukoyu]

cc @paulcallen @davidchisnall @prp @bodzhang @mikbras