ffmpegthumbnailer: unstable-2021-09-02 -> unstable-2022-02-18

Without the change build fails as:

    libffmpegthumbnailer/videothumbnailer.cpp: In member function 'void ffmpegthumbnailer::VideoThumbnailer::writeImage(...)':
    libffmpegthumbnailer/videothumbnailer.cpp:274:109: error: 'strerror' was not declared in this scope; did you mean 'stderr'?
      274 |             TraceMessage(ThumbnailerLogLevelError, std::string("Failed to stat file ") + videoFile + " (" + strerror(errno) + ")");

Update contains the only fix: https://github.com/dirkvdb/ffmpegthumbnailer/pull/213

pkgs/development/libraries/ffmpegthumbnailer/default.nix

@@ -3,13 +3,13 @@
 
 stdenv.mkDerivation rec {
   pname = "ffmpegthumbnailer";
-  version = "unstable-2021-09-02";
+  version = "unstable-2022-02-18";
 
   src = fetchFromGitHub {
     owner = "dirkvdb";
     repo = "ffmpegthumbnailer";
-    rev = "d92e191dd793b12cee0a0f685f5a8d8252988399";
-    sha256 = "1ysfq3g74b8ivivrdpfi4vm23d3cyc3rfla5i6y8q9aycis9xv6q";
+    rev = "3db9fe895b2fa656bb40ddb7a62e27604a688171";
+    sha256 = "0606pbg391l4s8mpyyalm9zrcnm75fwqdlrxy2gif9n21i2fm3rc";
   };
 
   nativeBuildInputs = [ cmake pkg-config ];