Fetches the SLRU segment via the new communicator.

The fetch is done not into a buffer as earlier, but directly into the
file.

test_runner/fixtures/neon_fixtures.py

@@ -4369,9 +4369,9 @@ class Endpoint(PgProtocol, LogUtils):
         # XXX: By checking for None, we enable the new communicator for all tests
         # by default
         if grpc or grpc is None:
-            config_lines += [f"neon.enable_new_communicator=on"]
+            config_lines += ["neon.use_communicator_worker=on"]
         else:
-            config_lines += [f"neon.enable_new_communicator=off"]
+            config_lines += ["neon.use_communicator_worker=off"]
 
         # Delete file cache if it exists (and we're recreating the endpoint)
         if USE_LFC:

test_runner/regress/test_normal_work.py

@@ -17,7 +17,9 @@ def check_tenant(
     config_lines = [
         f"neon.safekeeper_proto_version = {safekeeper_proto_version}",
     ]
-    endpoint = env.endpoints.create_start("main", tenant_id=tenant_id, config_lines=config_lines, grpc=True)
+    endpoint = env.endpoints.create_start(
+        "main", tenant_id=tenant_id, config_lines=config_lines, grpc=True
+    )
     # we rely upon autocommit after each statement
     res_1 = endpoint.safe_psql_many(
         queries=[