Add autosubmit code owners (#2990)

Follow up from [Formalize Cocoon Contributions](https://docs.google.com/document/d/1SxYP41p3CZY_BrUNb_zSfufvhUiSN3qxGl7QEjjTqHk/edit#heading=h.lgp3erb6u85n)

CODEOWNERS

@@ -4,6 +4,7 @@
 # These names are just suggestions. It is fine to have your changes
 # reviewed by someone else.
 
+auto_submit                                        @ricardoamador
 cipd_packages/codesign/**                          @XilaiZhang
 cipd_packages/device_doctor/**                     @yusuf-goog
 cipd_packages/doxygen/**                           @gspencergoog