doc: reorganized /cc list in alphabetical order

reorganized /cc list in alphabetical order in
onboarding-extras.md

Refs: nodejs#13621

doc/onboarding-extras.md

@@ -14,12 +14,12 @@
 | `lib/dgram` | @cjihrig, @mcollina |
 | `lib/domains` | @misterdjules |
 | `lib/fs`, `src/{fs,file}` | @nodejs/fs |
+| `lib/{_}http{*}` | @nodejs/http |
 | `lib/inspector.js`, `src/inspector_*` | @nodejs/v8-inspector |
 | `lib/internal/url`, `src/node_url` | @nodejs/url |
-| `lib/{_}http{*}` | @nodejs/http |
 | `lib/net` | @bnoordhuis, @indutny, @nodejs/streams |
-| `lib/{_}stream{*}` | @nodejs/streams |
 | `lib/repl` | @addaleax, @fishrock123 |
+| `lib/{_}stream{*}` | @nodejs/streams |
 | `lib/timers` | @fishrock123, @misterdjules |
 | `lib/util` | @bnoordhuis, @cjihrig, @evanlucas |
 | `lib/zlib` | @addaleax, @bnoordhuis, @indutny |
@@ -30,14 +30,13 @@
 | `tools/eslint`, `.eslintrc` | @not-an-aardvark, @silverwind, @trott |
 | async_hooks | @nodejs/async_hooks for bugs/reviews (+ @nodejs/diagnostics for API) |
 | performance | @nodejs/performance |
-| upgrading V8 | @nodejs/v8, @nodejs/post-mortem |
-| upgrading npm | @fishrock123, @MylesBorins |
+| platform specific | @nodejs/platform-{aix,arm,freebsd,macos,ppc,smartos,s390,windows} |
+| python code | @nodejs/python |
 | upgrading c-ares | @jbergstroem |
 | upgrading http-parser | @jbergstroem, @nodejs/http |
 | upgrading libuv | @saghul |
-| python code | @nodejs/python |
-| platform specific | @nodejs/platform-{aix,arm,freebsd,macos,ppc,smartos,s390,windows} |
-
+| upgrading npm | @fishrock123, @MylesBorins |
+| upgrading V8 | @nodejs/v8, @nodejs/post-mortem |
 
 When things need extra attention, are controversial, or `semver-major`: @nodejs/ctc