Cleanup: convert caml_format to .res.

Author: cristianoc

CHANGELOG.md

@@ -43,6 +43,7 @@
 - Fix `-nostdlib` internal compiler option. https://github.com/rescript-lang/rescript-compiler/pull/6824
 - Remove a number of ast nodes never populated by the .res parser, and resulting dead code. https://github.com/rescript-lang/rescript-compiler/pull/6830
 - Remove coercion with 2 types from internal representation. Coercion `e : t1 :> t2` was only supported in `.ml` syntax and never by the `.res` parser. https://github.com/rescript-lang/rescript-compiler/pull/6829 
+- Convert `caml_format` to `.res`. https://github.com/rescript-lang/rescript-compiler/pull/6834
 
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