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/frameworks/sumstats/basic.zeek

@@ -1,7 +1,9 @@
-# @TEST-EXEC: btest-bg-run standalone zeek %INPUT
-# @TEST-EXEC: btest-bg-wait 10
+# @TEST-EXEC: btest-bg-run standalone zeek -b %INPUT
+# @TEST-EXEC: btest-bg-wait 15
 # @TEST-EXEC: btest-diff standalone/.stdout
 
+@load base/frameworks/sumstats
+
 redef exit_only_after_terminate=T;
 
 event zeek_init() &priority=5