gnu: Remove FFmpeg 4.2.

* gnu/packages/video.scm (ffmpeg-4.2): Remove variable.

gnu/packages/video.scm

@@ -1612,27 +1612,6 @@ convert and stream audio and video.  It includes the libavcodec
 audio/video codec library.")
     (license license:gpl2+)))
 
-;; ungoogled-chromium crashes with ffmpeg 4.3, so stick with this version for
-;; now.  See <https://issues.guix.gnu.org/41987>.
-(define-public ffmpeg-4.2
-  (package
-    (inherit ffmpeg)
-    (version "4.2.3")
-    (source (origin
-              (method url-fetch)
-              (uri (string-append "https://ffmpeg.org/releases/ffmpeg-"
-                                  version ".tar.xz"))
-              (sha256
-               (base32
-                "0cddkb5sma9dzy8i59sfls19rhjlq40zn9mh3x666dqkxl5ckxlx"))))
-    (arguments
-     (substitute-keyword-arguments (package-arguments ffmpeg)
-       ((#:configure-flags flags)
-        `(delete "--enable-librav1e" ,flags))))
-    (inputs (fold alist-delete
-                  (package-inputs ffmpeg)
-                  '("rav1e")))))
-
 (define-public ffmpeg-3.4
   (package
     (inherit ffmpeg)