Don't pass PYTHON_BINARY to CSFLE setup

Author: NoahStapp

.evergreen/setup-encryption.sh

@@ -52,6 +52,9 @@ ls -la libmongocrypt
 ls -la libmongocrypt/nocrypto
 
 if [ -z "${SKIP_SERVERS:-}" ]; then
+    PYTHON_BINARY_OLD=${PYTHON_BINARY}
+    export PYTHON_BINARY=""
     bash "${DRIVERS_TOOLS}"/.evergreen/csfle/setup-secrets.sh
+    export PYTHON_BINARY=$PYTHON_BINARY_OLD
     bash "${DRIVERS_TOOLS}"/.evergreen/csfle/start-servers.sh
 fi