theharvester: fix test (#5467)

The pgp data source does not work (at least not at the moment) because
the source code hard codes pgp.rediris.es:11371 which is down. It's not
something we should fix on our side. Instead, we switch to the google
data source which should be much more reliable.

Formula/theharvester.rb

@@ -34,7 +34,7 @@ def install
   end
 
   test do
-    output = shell_output("#{bin}/theharvester -d brew.sh -l 1 -b pgp 2>&1")
+    output = shell_output("#{bin}/theharvester -d brew.sh -l 1 -b google 2>&1")
     assert_match "security@brew.sh", output
   end
 end