chore(default-config): allowlist common crawl (#753)

This may seem strange, but allowlisting common crawl means that scrapers
have less incentive to scrape because they can just grab the data from
common crawl instead of scraping it again.

data/crawlers/_allow-good.yaml

@@ -6,4 +6,5 @@
 - import: (data)/crawlers/internet-archive.yaml
 - import: (data)/crawlers/kagibot.yaml
 - import: (data)/crawlers/marginalia.yaml
-- import: (data)/crawlers/mojeekbot.yaml
+- import: (data)/crawlers/mojeekbot.yaml
+- import: (data)/crawlers/commoncrawl.yaml

data/crawlers/commoncrawl.yaml

@@ -0,0 +1,12 @@
+- name: common-crawl
+  user_agent_regex: CCBot
+  action: ALLOW
+  # https://index.commoncrawl.org/ccbot.json
+  remote_addresses:
+    [
+      "2600:1f28:365:80b0::/60",
+      "18.97.9.168/29",
+      "18.97.14.80/29",
+      "18.97.14.88/30",
+      "98.85.178.216/32",
+    ]