Add net-protocol license to allowed list

This is the same BSD license as Ruby:

1. https://github.com/ruby/net-protocol/blob/master/LICENSE.txt
2. https://github.com/ruby/ruby/blob/master/BSDL

config/dependency_decisions.yml

@@ -331,3 +331,9 @@
     :why: https://github.com/xijo/reverse_markdown/blob/master/LICENSE
     :versions: []
     :when: 2021-02-03 08:47:28.792907000 Z
+- - :approve
+  - net-protocol
+  - :who: Stan Hu
+    :why: "This license is the same as the Ruby license (BSD): https://github.com/ruby/net-protocol/blob/master/LICENSE.txt"
+    :versions: []
+    :when: 2021-03-18 00:00:46.124036000 Z