Update codeql.yml

opam needs to be told "yes"

.github/workflows/codeql.yml

@@ -74,8 +74,9 @@ jobs:
         sudo apt-get -qq install -y libc6-dev-amd64-cross libgcc-s1-amd64-cross libtbb-dev libfl-dev ocaml camlp4 ocaml-findlib camlidl binutils-dev libiberty-dev libprotobuf-dev ocamlbuild opam erlang erlang-base libprotoc-dev ocamlweb binfmtc llvm llvm-dev clang llvm-runtime libllvm-ocaml-dev exuberant-ctags libparse-exuberantctags-perl libcamomile-ocaml-dev libgettext-ocaml libgettext-ocaml-dev z3 libz3-dev libz3-java libz3-jni libbatteries-ocaml-dev ocaml-batteries-included liblablgl-ocaml liblablgl-ocaml-dev liblablgtk2-ocaml liblablgtk2-ocaml-dev liblablgtk2-gnome-ocaml liblablgtk2-gnome-ocaml-dev liblablgtk2-gl-ocaml liblablgtk2-gl-ocaml-dev liblablgtk-extras-ocaml-dev liblablgtk3-ocaml liblablgtk3-ocaml-dev liblablgtksourceview3-ocaml liblablgtksourceview3-ocaml-dev liblablgtkspell3-ocaml liblablgtkspell3-ocaml-dev dh-make libasprintf-dev libgettextpo-dev
         sudo apt-get install -y gcj-jdk || echo "will just have to do without gcj..."
         which -a opam
-        opam init
-        opam install xmlm ulex easy-format camomile gettext-camomile camlidl
+        opam -y init
+        eval $(opam env --switch=default)
+        opam -y install xmlm ulex easy-format camomile gettext-camomile camlidl
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL