Release script fixes

Author: ncough

.github/workflows/release.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-20.04
 
     env:
       OPAMJOBS: 2

tools/release.sh

@@ -24,7 +24,7 @@ TMPDIR=$(mktemp -d)
 eval $(opam config env)
 echo OCaml is at $(which ocaml)
 echo "Looking in the dev-repo for the current list of dependencies"
-opam pin add bap --dev-repo --yes -n
+opam pin add bap https://github.com/UQ-PAC/bap.git --yes -n
 echo "Installing System dependenices"
 opam depext bap --yes
 echo "Installing OCaml dependenices"