message: doc: replace outdated OpenSSL comment in test README
diff: @@ -116,7 +116,7 @@ Basic code to support P2P connectivity to a bitcoind.
  Utilities for manipulating transaction scripts (originally from python-bitcoinlib)
  #### [test_framework/key.py](test_framework/key.py)
  -Wrapper around OpenSSL EC_Key (originally from python-bitcoinlib)
  +Test-only secp256k1 elliptic curve implementation
  #### [test_framework/bignum.py](test_framework/bignum.py)
  Helpers for script.py
  