Use upstream instead of local version of z3 4.15.3

Author: nmouha

nix/cbmc/default.nix

@@ -29,11 +29,19 @@ buildEnv {
       });
       litani = callPackage ./litani.nix { }; # 1.29.0
       cbmc-viewer = callPackage ./cbmc-viewer.nix { }; # 3.11
+      z3 = z3.overrideAttrs (old: rec {
+        version = "4.15.3";
+        src = fetchFromGitHub {
+          owner = "Z3Prover";
+          repo = "z3";
+          rev = "z3-4.15.3";
+          hash = "sha256-Lw037Z0t0ySxkgMXkbjNW5CB4QQLRrrSEBsLJqiomZ4=";
+        };
+      });
 
       inherit
-        cadical # 2.1.3
-        bitwuzla # 0.8.2
-        ninja # 1.12.1
-        z3; # 4.15.3
+        cadical#2.1.3
+        bitwuzla# 0.8.2
+        ninja; # 1.12.1
     };
 }