🔧(backend) configure request.summary logger

The request.summary logger is used by dockerflow. The INFO level is
always empty and is used everytime the liveness or readiness endpoint
are fetch.

src/backend/impress/settings.py

@@ -1034,6 +1034,13 @@ class Base(Configuration):
                 ),
                 "propagate": True,
             },
+            "request.summary": {
+                "level": values.Value(
+                    "WARNING",
+                    environ_name="LOGGING_LEVEL_REQUEST_SUMMARY",
+                    environ_prefix=None,
+                )
+            },
         },
     }