Replace $Call in babel-traverse libdef with conditional type (#41736)

Summary:
Pull Request resolved: #41736

Changelog: [Internal]

Reviewed By: gkz

Differential Revision: D51735062

fbshipit-source-id: 942264cdc9f71e4aaa6f730d68f5a2a6e2fc7493

flow-typed/npm/babel-traverse_v7.x.x.js

@@ -293,9 +293,6 @@ declare module '@babel/traverse' {
     dereference(): void;
   }
 
-  declare function getNodePathType(node: BabelNode): NodePath<>;
-  declare function getNodePathType(nodes: Array<BabelNode>): Array<NodePath<>>;
-
   declare type Opts = {...};
 
   declare export class NodePath<+TNode: BabelNode = BabelNode> {
@@ -733,7 +730,7 @@ declare module '@babel/traverse' {
     get<TKey: $Keys<TNode>>(
       key: TKey,
       context?: boolean | TraversalContext,
-    ): $Call<typeof getNodePathType, TNode[TKey]>;
+    ): TNode[TKey] extends BabelNode ? NodePath<> : Array<NodePath<>>;
 
     get(
       key: string,