General btest cleanup

- Use `-b` most everywhere, it will save time.

- Start some intel tests upon the input file being fully read instead of
  at an arbitrary time.

- Improve termination condition for some sumstats/cluster tests.

- Filter uninteresting output from some supervisor tests.

- Test for `notice_policy.log` is no longer needed.

testing/btest/scripts/base/files/entropy/basic.test

@@ -1,6 +1,7 @@
-# @TEST-EXEC: zeek -r $TRACES/http/get.trace %INPUT
+# @TEST-EXEC: zeek -b -r $TRACES/http/get.trace %INPUT
 # @TEST-EXEC: btest-diff .stdout
 
+@load base/protocols/http
 
 event file_new(f: fa_file)
 	{
@@ -10,4 +11,4 @@ event file_new(f: fa_file)
 event file_entropy(f: fa_file, ent: entropy_test_result)
 	{
 	print ent;
-	}
+	}