Merge #10759: Fix multi_rpc test for hosts that dont default to utf8

bc7d103 Fix multi_rpc test for hosts that dont default to utf8 (Matt Corallo)

Tree-SHA512: 7644b1f50d4010a08aed5d1c87ab7326af9c109ac05dfbfc4bb6d5a19ace7997ef9cdd64d4301072f1106225de6d3aacccb17f53043b55ba61f5723c2b65af30

Author: MarcoFalke

test/functional/test_framework/util.py

@@ -236,7 +236,7 @@ def get_auth_cookie(datadir, n):
     user = None
     password = None
     if os.path.isfile(os.path.join(datadir, "bitcoin.conf")):
-        with open(os.path.join(datadir, "bitcoin.conf"), 'r') as f:
+        with open(os.path.join(datadir, "bitcoin.conf"), 'r', encoding='utf8') as f:
             for line in f:
                 if line.startswith("rpcuser="):
                     assert user is None  # Ensure that there is only one rpcuser line