doc: use serial comma in http docs

Refs: #11321
Refs: #17384

PR-URL: #43026
Reviewed-By: Rich Trott <[email protected]>
Reviewed-By: Mohammed Keyvanzadeh <[email protected]>

Author: tniessen

doc/api/http.md

@@ -2222,7 +2222,7 @@ changes:
 An `IncomingMessage` object is created by [`http.Server`][] or
 [`http.ClientRequest`][] and passed as the first argument to the [`'request'`][]
 and [`'response'`][] event respectively. It may be used to access response
-status, headers and data.
+status, headers, and data.
 
 Different from its `socket` value which is a subclass of {stream.Duplex}, the
 `IncomingMessage` itself extends {stream.Readable} and is created separately to
@@ -2962,8 +2962,8 @@ added: v0.1.13
 changes:
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41263
-    description: The `requestTimeout`, `headersTimeout`, `keepAliveTimeout` and
-                 `connectionsCheckingInterval` are supported now.
+    description: The `requestTimeout`, `headersTimeout`, `keepAliveTimeout`, and
+                 `connectionsCheckingInterval` options are supported now.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/42163
     description: The `noDelay` option now defaults to `true`.