firefox: drop maintainership

After the recent wrapper and plugin purge outbreak where as the only
active listed maintainer of the package I didn't even get a chance to
comment (e.g. via comment or review request) I do not want to continue
maintaining this package anymore.

pkgs/applications/networking/browsers/firefox/packages.nix

@@ -27,7 +27,7 @@ rec {
     meta = {
       description = "A web browser built from Firefox source tree";
       homepage = "http://www.mozilla.com/en-US/firefox/";
-      maintainers = with lib.maintainers; [ eelco andir ];
+      maintainers = with lib.maintainers; [ eelco ];
       platforms = lib.platforms.unix;
       badPlatforms = lib.platforms.darwin;
       broken = stdenv.buildPlatform.is32bit; # since Firefox 60, build on 32-bit platforms fails with "out of memory".
@@ -51,7 +51,7 @@ rec {
     meta = {
       description = "A web browser built from Firefox Extended Support Release source tree";
       homepage = "http://www.mozilla.com/en-US/firefox/";
-      maintainers = with lib.maintainers; [ eelco andir ];
+      maintainers = with lib.maintainers; [ eelco ];
       platforms = lib.platforms.unix;
       badPlatforms = lib.platforms.darwin;
       broken = stdenv.buildPlatform.is32bit; # since Firefox 60, build on 32-bit platforms fails with "out of memory".