Remove DNS Graph CRuX crawler from example config

Our current build machine runs out of memory for this crawler, so do not
include in the weekly dumps for now.

Author: m-appel

config.json.example

@@ -102,7 +102,6 @@
             "iyp.crawlers.openintel.crux",
             "iyp.crawlers.openintel.dnsgraph_nl",
             "iyp.crawlers.openintel.dnsgraph_rdns",
-            "iyp.crawlers.openintel.dnsgraph_crux",
             "iyp.crawlers.cloudflare.dns_top_locations",
             "iyp.crawlers.cloudflare.dns_top_ases",
             "iyp.crawlers.ooni.facebookmessenger",