Document syntax for `module type of`

[sapristi]

Hello,
this issue is just a reminder that some documentation about module type of (cf https://caml.inria.fr/pub/docs/manual-ocaml/moduletypeof.html) would be welcome.
I could find an example usage here: rescript-lang/rescript#2765

Cheers,

[ryyppy]

Hmm, not sure where to put this... probably somewhere near the Extending Modules section

[sapristi]

Well I can see that an example was added in the doc, so I guess we can close this ?
https://rescript-lang.org/docs/manual/latest/module#extending-module-signatures

[ryyppy]

right, i think this was actually already there? will close it then.