signal-desktop: ringrtc depends on libpulseaudio

voice/video calls should now work, fixing #98082

pkgs/applications/networking/instant-messengers/signal-desktop/default.nix

@@ -4,7 +4,7 @@
 , libXext, libXfixes, libXrender, libXtst, libXScrnSaver, nss, nspr, alsaLib
 , cups, expat, libuuid, at-spi2-core, libappindicator-gtk3
 # Runtime dependencies:
-, systemd, libnotify, libdbusmenu
+, systemd, libnotify, libdbusmenu, libpulseaudio
 # Unfortunately this also overwrites the UI language (not just the spell
 # checking language!):
 , hunspellDicts, spellcheckerLanguage ? null # E.g. "de_DE"
@@ -122,6 +122,7 @@ in stdenv.mkDerivation rec {
       --replace /opt/Signal/signal-desktop $out/bin/signal-desktop
 
     autoPatchelf --no-recurse -- $out/lib/Signal/
+    patchelf --add-needed ${libpulseaudio}/lib/libpulse.so $out/lib/Signal/resources/app.asar.unpacked/node_modules/ringrtc/build/linux/libringrtc.node
   '';
 
   # Tests if the application launches and waits for "Link your phone to Signal Desktop":