peek: use ffmpeg 4

See migrate away from ffmpeg_3 #120705.

pkgs/applications/video/peek/default.nix

@@ -16,7 +16,7 @@
 , glib
 , cairo
 , keybinder3
-, ffmpeg_3
+, ffmpeg
 , python3
 , libxml2
 , gst_all_1
@@ -66,7 +66,7 @@ stdenv.mkDerivation rec {
   '';
 
   preFixup = ''
-    gappsWrapperArgs+=(--prefix PATH : ${lib.makeBinPath [ which ffmpeg_3 gifski ]})
+    gappsWrapperArgs+=(--prefix PATH : ${lib.makeBinPath [ which ffmpeg gifski ]})
   '';
 
   passthru = {
@@ -79,7 +79,7 @@ stdenv.mkDerivation rec {
   meta = with lib; {
     homepage = "https://github.com/phw/peek";
     description = "Simple animated GIF screen recorder with an easy to use interface";
-    license = licenses.gpl3;
+    license = licenses.gpl3Plus;
     maintainers = with maintainers; [ puffnfresh ];
     platforms = platforms.linux;
   };