Remove unnecessary docs and config keys (#2845)

docs/en/setup/backend/dynamic-config.md

@@ -44,10 +44,6 @@ configuration:
     port: 8848
     # Nacos Configuration Group
     group: 'skywalking'
-    # Dynamically configured keys
-    dataIds:
-      - receiver-trace.default.slowDBAccessThreshold
-      # - other-key
     # Unit seconds, sync period. Default fetch every 60 seconds.
     period : 60
     # the name of current cluster, set the name if you want to upstream system known.

oap-server/server-configuration/configuration-nacos/src/test/resources/application.yml

@@ -27,10 +27,6 @@ configuration:
     port: 8848
     # Nacos Configuration Group
     group: 'skywalking'
-    # Dynamically configured keys
-    dataIds:
-      - test-module.default.testKey
-      # - other-key
     # Unit seconds, sync period. Default fetch every 60 seconds.
     period: 1
     # the name of current cluster, set the name if you want to upstream system known.