cloudflare-warp: bind package location as /usr to warp-taskbar

The warp-taskbar package wants to access `/usr/share/warp/images` and
crashes if it does not exist. As a workaround, bind the package out
path as `/usr` so that the process can find the image directory at
the expected location.

pkgs/tools/networking/cloudflare-warp/default.nix

@@ -73,6 +73,12 @@ stdenv.mkDerivation rec {
     substituteInPlace $out/lib/systemd/user/warp-taskbar.service \
       --replace "ExecStart=" "ExecStart=$out"
 
+    cat >>$out/lib/systemd/user/warp-taskbar.service <<EOF
+
+    [Service]
+    BindReadOnlyPaths=$out:/usr:
+    EOF
+
     runHook postInstall
   '';