owl-lisp: Use dash for tests

On aarch64-linux the test fail to terminate, with bash printing a
message like this over and over again:

tests/run: line 63: wait: pid 105 is not a child of this shell

Running in GDB reveals that the is stuck in an infinite loop in
wait_for_background_pids waiting for a child that is no longer there,
suggesting that it's a bug in Bash.

Work around it for now by running tests in DASH instead.

pkgs/by-name/ow/owl-lisp/package.nix

@@ -3,6 +3,7 @@
   stdenv,
   fetchFromGitLab,
   which,
+  dash,
 }:
 
 stdenv.mkDerivation rec {
@@ -16,7 +17,17 @@ stdenv.mkDerivation rec {
     hash = "sha256-GfvOkYLo8fgAvGuUa59hDy+sWJSwyntwqMO8TAK/lUo=";
   };
 
-  nativeBuildInputs = [ which ];
+  nativeBuildInputs = [
+    which
+    dash
+  ];
+
+  # Tests fail with bash, replacing with dash seems to work around it
+  # FIXME: Why?
+  postPatch = ''
+    substituteInPlace Makefile \
+      --replace-fail 'sh tests/run' 'dash tests/run'
+  '';
 
   makeFlags = [
     "PREFIX=${placeholder "out"}"