cvise: disable blanket -Werror

`-Werror` flag usually causes build failures due to minor changes in
compiler versions. They might be useful for developers themselves but
are rarely useful for distributions.

For example right now `cvise` fails to compile on `gcc-13` due to
a `gcc` infelicity: https://gcc.gnu.org/PR107488

While this concrete instance is a compiler bug generally `-Werror` makes
users' lives harder. Specific `-Werror=<foo>` are better way to prevent
certain classes of bugs.

The change removes blanket `-Werror` with a `substituteInPlace` call.

pkgs/development/tools/misc/cvise/default.nix

@@ -32,6 +32,11 @@ buildPythonApplication rec {
   ];
 
   postPatch = ''
+    # Avoid blanket -Werror to evade build failures on less
+    # tested compilers.
+    substituteInPlace CMakeLists.txt \
+      --replace " -Werror " " "
+
     # 'cvise --command=...' generates a script with hardcoded shebang.
     substituteInPlace cvise.py \
       --replace "#!/bin/bash" "#!${bash}/bin/bash"