Match build openssl version with README

[cameronelliott]

This is what happens when you try to follow the README:

c@intel12400 ~/dtls-fuzzer (fix-openssl-ver)> LD_LIBRARY_PATH=suts/openssl-1.1.1b/ java -jar target/dtls-fuzzer.jar @args/
openssl/learn_openssl_server_psk -test examples/tests/servers/psk
05:03:59 [main] INFO : Main - Processing command state-fuzzer-server
05:03:59 [main] INFO : Main - Running test runner
05:04:00 [main] INFO : ProcessHandler - Command to launch SUT: /home/c/dtls-fuzzer/suts/openssl-1.1.1k/apps/openssl s_server -psk 1234 -key /home/c/dtls-fuzzer/experiments/keystore/rsa2048_key.pem -cert /home/c/dtls-fuzzer/experiments/keystore/rsa2048_cert.pem -CAfile /home/c/dtls-fuzzer/experiments/keystore/rsa2048_cert.pem -accept 27039 -dtls1_2 -mtu 5000
05:04:00 [main] ERROR: ProcessHandler - Couldn't start process due to exec:
 java.io.IOException: Cannot run program "/home/c/dtls-fuzzer/suts/openssl-1.1.1k/apps/openssl": error=2, No such file or directory

Maybe the plan is to switch to 1.1.1k for the Readme example, but it seems other fixes need to
be made to the Readme to get things working. (in my experience)

So, I am submitting a few PRs to get things working with 1.1.1b, rather than mixing 1.1.1b->1.1.1k upgrade AND getting basic Readme example working.