Fixed CI

Author: ankane

.github/workflows/build.yml

@@ -6,6 +6,8 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - uses: ocaml/setup-ocaml@v2
+        with:
+          ocaml-compiler: 4.14
       - uses: ankane/setup-postgres@v1
         with:
           database: pgvector_ocaml_test