OCaml API: update opam file for hacl-star-raw

[victor-dumitrescu]

Updates opam file with changes made during review on ocaml/opam-repository:

• specifies bytecode only not supported (can't build on s390x with OCaml 5) (discussion)
• removes outdated CI exceptions (discussion)

[coveralls]

Pull Request Test Coverage Report for Build 4636620220

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 53.441%

---

Totals
Change from base Build 4617908890:	0.0%
Covered Lines:	30398
Relevant Lines:	56881

---

💛 - Coveralls