old_contents: known_chains = {"BTS" : {"chain_id" : "4018d7844c78f6a6c41c6a552b898022310fc5dec06da467ee7905a8dad512c8",
                           "core_symbol" : "BTS",
                           "prefix" : "BTS"},
                  "GPH" : {"chain_id" : "b8d1603965b3eb1acba27e62ff59f74efa3154d43a4188d381088ac7cdf35539",
                           "core_symbol" : "CORE",
                           "prefix" : "GPH"},
                  }
  
new_contents: known_chains = {"BTS" : {"chain_id" : "4018d7844c78f6a6c41c6a552b898022310fc5dec06da467ee7905a8dad512c8",
                           "core_symbol" : "BTS",
                           "prefix" : "BTS"},
                  "GPH" : {"chain_id" : "b8d1603965b3eb1acba27e62ff59f74efa3154d43a4188d381088ac7cdf35539",
                           "core_symbol" : "CORE",
                           "prefix" : "GPH"},
                  "TEST" : {"chain_id" : "39f5e2ede1f8bc1a3a54a7914414e3779e33193f1f5693510e73cb7a87617447",
                            "core_symbol" : "TEST",
                            "prefix" : "TEST"}
                  }
  
subject: Add testnet-chain