Added a guide on how to use auto_explain

docker-compose.yml

@@ -7,6 +7,14 @@ services:
     image: postgres:14-alpine
     ## Use the following image instead if you want to use PGroonga
     # image: groonga/pgroonga:3.1.1-alpine-14
+    ## Uncomment and tweak these values if necessary
+    # command:
+    #   - -c
+    #   - session_preload_libraries=auto_explain
+    #   - -c
+    #   - auto_explain.log_min_duration=250ms
+    #   - -c
+    #   - auto_explain.log_analyze=on
     restart: unless-stopped
     environment:
       POSTGRES_DB: akkoma