fix: doc path (nodejs#1157)

Co-authored-by: hanquliu <[email protected]>

Author: 2 people

docsify/sidebar.md

@@ -16,7 +16,7 @@
   * [MockErrors](/docs/api/MockErrors.md "Undici API - MockErrors")
   * [API Lifecycle](/docs/api/api-lifecycle.md "Undici API - Lifecycle")
 * Best Practices
-  * [Proxy](docs/best-practices/proxy.md "Connecting through a proxy")
-  * [Client Certificate](docs/best-practices/client-certificate.md "Connect using a client certificate")
-  * [Writing Tests](docs/best-practices/writing-tests.md "Using Undici inside tests")
-  * [Mocking Request](docs/best-practices/mocking-request.md "Using Undici inside tests")
+  * [Proxy](/docs/best-practices/proxy.md "Connecting through a proxy")
+  * [Client Certificate](/docs/best-practices/client-certificate.md "Connect using a client certificate")
+  * [Writing Tests](/docs/best-practices/writing-tests.md "Using Undici inside tests")
+  * [Mocking Request](/docs/best-practices/mocking-request.md "Using Undici inside tests")