Add a Dependabot config file

.github/dependabot.yml

@@ -0,0 +1,22 @@
+# This file is part of masscanned.
+# Copyright 2021 - The IVRE project
+#
+# Masscanned is free software: you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# Masscanned is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+# License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Masscanned. If not, see <http://www.gnu.org/licenses/>.
+
+version: 2
+updates:
+- package-ecosystem: cargo
+  directory: "/"
+  schedule:
+    interval: daily