make OperationKind public (#4489)

Fix #4410

`OperationKind` was already used in a public field but the type itself
was still private.

.changesets/fix_geal_expose_operationkind.md

@@ -0,0 +1,5 @@
+### make OperationKind public ([Issue #4410](https://github.com/apollographql/router/issues/4410))
+
+`OperationKind` was already used in a public field but the type itself was still private.
+
+By [@Geal](https://github.com/Geal) in https://github.com/apollographql/router/pull/4489

apollo-router/src/query_planner/mod.rs

@@ -5,7 +5,7 @@
 pub(crate) use bridge_query_planner::*;
 pub(crate) use caching_query_planner::*;
 
-pub(crate) use self::fetch::OperationKind;
+pub use self::fetch::OperationKind;
 
 mod bridge_query_planner;
 mod caching_query_planner;

apollo-router/src/services/mod.rs

@@ -10,6 +10,7 @@ use crate::graphql::Request;
 use crate::http_ext;
 pub use crate::http_ext::TryIntoHeaderName;
 pub use crate::http_ext::TryIntoHeaderValue;
+pub use crate::query_planner::OperationKind;
 pub(crate) use crate::services::execution::Request as ExecutionRequest;
 pub(crate) use crate::services::execution::Response as ExecutionResponse;
 pub(crate) use crate::services::query_planner::Request as QueryPlannerRequest;