seasocks: fix build w/glibc-2.34

Failing Hydra build: https://hydra.nixos.org/build/155145624

pkgs/development/libraries/seasocks/default.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, fetchFromGitHub, cmake, python3, zlib }:
+{ lib, stdenv, fetchFromGitHub, cmake, python3, zlib, catch2 }:
 
 stdenv.mkDerivation rec {
   pname = "seasocks";
@@ -11,9 +11,15 @@ stdenv.mkDerivation rec {
     sha256 = "1f9a3mx3yjmr5qry4rc1c7mrx3348iifxm7d8sj8yd41kqnzmfv4";
   };
 
+  postPatch = ''
+    cp ${catch2}/include/catch2/catch.hpp src/test/c/catch/catch2/catch.hpp
+  '';
+
   nativeBuildInputs = [ cmake ];
   buildInputs = [ zlib python3 ];
 
+  doCheck = true;
+
   meta = with lib; {
     homepage = "https://github.com/mattgodbolt/seasocks";
     description = "Tiny embeddable C++ HTTP and WebSocket server";