Bump ocaml/setup-ocaml from 3.4.6 to 3.4.8 (rescript-lang#8125)

Bumps [ocaml/setup-ocaml](https://github.com/ocaml/setup-ocaml) from 3.4.6 to 3.4.8.
- [Release notes](https://github.com/ocaml/setup-ocaml/releases)
- [Commits](ocaml/setup-ocaml@v3.4.6...v3.4.8)

---
updated-dependencies:
- dependency-name: ocaml/setup-ocaml
  dependency-version: 3.4.8
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -173,7 +173,7 @@ jobs:
           key: ${{ env.opam_cache_key }}
 
       - name: Use OCaml ${{matrix.ocaml_compiler}}
-        uses: ocaml/setup-ocaml@v3.4.6
+        uses: ocaml/setup-ocaml@v3.4.8
         if: steps.cache-opam-env.outputs.cache-hit != 'true'
         with:
           ocaml-compiler: ${{matrix.ocaml_compiler}}