Bump core from 86cc361 to f4c8710 (#1500)

Bumps [core](https://github.com/microsoft/typespec) from `86cc361` to
`f4c8710`.
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/microsoft/typespec/commit/f4c8710673139b1d05cb77717f897b717efa1d7d"><code>f4c8710</code></a>
Fix set response doc when an envelope (<a
href="https://redirect.github.com/microsoft/typespec/issues/4322">#4322</a>)</li>
<li><a
href="https://github.com/microsoft/typespec/commit/d2ac9958422db48acd818340c6b8ae069da0cf41"><code>d2ac995</code></a>
Extract source resolution logic into its own source loader (<a
href="https://redirect.github.com/microsoft/typespec/issues/4324">#4324</a>)</li>
<li><a
href="https://github.com/microsoft/typespec/commit/dde8dc0ca70578e81bcd435f09e03bb8d84bd082"><code>dde8dc0</code></a>
Add api extractor for openapi package and fix issues (<a
href="https://redirect.github.com/microsoft/typespec/issues/4354">#4354</a>)</li>
<li>See full diff in <a
href="https://github.com/microsoft/typespec/compare/86cc361bf0a0ed29dbe80613cc2435331786cdce...f4c8710673139b1d05cb77717f897b717efa1d7d">compare
view</a></li>
</ul>
</details>
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packages/samples/test/output/core/documentation/@azure-tools/typespec-autorest/openapi.json

@@ -98,7 +98,7 @@
             }
           },
           "404": {
-            "description": "The server cannot find the requested resource.",
+            "description": "Not found",
             "schema": {
               "$ref": "#/definitions/NotFoundWithDocsResp"
             }