opentelemetry-cpp: fix CMake target include dirs (#328851)

pkgs/by-name/op/opentelemetry-cpp/package.nix

@@ -66,6 +66,11 @@ stdenv.mkDerivation (finalAttrs: {
 
   outputs = [ "out" "dev" ];
 
+  postInstall = ''
+    substituteInPlace $out/lib/cmake/opentelemetry-cpp/opentelemetry-cpp-target.cmake \
+      --replace-fail "\''${_IMPORT_PREFIX}/include" "$dev/include"
+  '';
+
   passthru.updateScript = nix-update-script { };
 
   meta = {