message: Docs: Fix typo in shadowing config
diff: @@ -263,8 +263,8 @@ Shadow
  The router is capable of shadowing traffic from one cluster to another. The current implementation
  is "fire and forget," meaning Envoy will not wait for the shadow cluster to respond before returning
  -the response from the primary cluster. All normal statistics are collected however for the shadow
  -cluster making thie feature useful for testing.
  +the response from the primary cluster. All normal statistics are collected for the shadow
  +cluster making this feature useful for testing.
  During shadowing, the host/authority header is altered such that *-shadow* is appended. This is
  useful for logging. For example, *cluster1* becomes *cluster1-shadow*.
  