configure {black,white}hole ports on pythontest

Replaces functionality of blackhole.snakebite.net and whitehole.snakebite.net

Ref: python/cpython#75743
Ref: python/cpython#109060

Author: ewdurbin

pillar/base/firewall/snakebite.sls

@@ -0,0 +1,9 @@
+firewall:
+  snakebite-blackhole-tcp:
+    raw: -A INPUT -p tcp --destination-port 56666 -j DROP
+  snakebite-blackhole-udp:
+    raw: -A INPUT -p udp --destination-port 56666 -j DROP
+  snakebite-whitehole-tcp:
+    raw: -A INPUT -p tcp --destination-port 56667 -j RETURN
+  snakebite-whitehole-udp:
+    raw: -A INPUT -p udp --destination-port 56667 -j RETURN

pillar/prod/top.sls

@@ -109,6 +109,7 @@ base:
     - match: nodegroup
     - firewall.http
     - firewall.ftp
+    - firewall.snakebite
 
   'web-pypa':
     - match: nodegroup