[install] update script versions to 3.4

bin/installdumux.py

@@ -18,7 +18,7 @@ parser.add_argument('--dune-version',
                     default="2.7",
                     help='Dune version to be checked out.')
 parser.add_argument('--dumux-version',
-                    default="3.3",
+                    default="3.4",
                     help='Dumux version to be checked out.')
 args = vars(parser.parse_args())
 

bin/installexternal.py

@@ -75,7 +75,7 @@ options.add_argument('--download', action="store_true", default=False,
 
 parser.add_argument('--dune_branch', default="releases/2.7",
                      help='Dune branch to be checked out.')
-parser.add_argument('--dumux_branch', default="releases/3.3",
+parser.add_argument('--dumux_branch', default="releases/3.4",
                      help='Dumux branch to be checked out.')
 parser.add_argument('--opm_branch', default="release/2020.10",
                      help='Opm branch to be checked out.')