DEV: prevents heisentest in processor spec (#12066)

This test failure was caused by rails calling `.debug` on our FakeLogger which was not supporting it, resulting in more errors than what the test was expecting.

spec/support/fake_logger.rb

@@ -6,6 +6,7 @@ class FakeLogger
   def initialize
     @warnings = []
     @errors = []
+    @debug = []
     @infos = []
     @fatals = []
   end
@@ -26,6 +27,10 @@ class FakeLogger
     @fatals << message
   end
 
+  def debug(message)
+    @debug << message
+  end
+
   def formatter
   end
 end