Fix operation.setContext() type

[henryqdineen]

I noticed couple issues with the Operation.setContext() types that I try to fix in this PR:

• The function is a void and does not return DefaultContext
• The type was missing an override where it accepts an updater function.

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[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: d2c81dc281ecbec65201f951ab4fde2ede7b47d1

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

| Name | Type | | -------------- | ----- | | @apollo/client | Patch |

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[phryneas]

While we're at it, could you please also add these adjustments?

--- a/src/link/utils/createOperation.ts
+++ b/src/link/utils/createOperation.ts
@@ -5,14 +5,14 @@ export function createOperation(
   operation: GraphQLRequest
 ): Operation {
   let context = { ...starting };
-  const setContext = (next: any) => {
+  const setContext: Operation["setContext"] = (next) => {
     if (typeof next === "function") {
       context = { ...context, ...next(context) };
     } else {
       context = { ...context, ...next };
     }
   };
-  const getContext = () => ({ ...context });
+  const getContext: Operation["getContext"] = () => ({ ...context });

   Object.defineProperty(operation, "setContext", {
     enumerable: false,

[henryqdineen]

Just made the adjustments. Thanks! No rush.