📈 Update parser benchmark comparison

* strip out ruby/object, to load yml without loading Net::IMAP objects.
* delete and ignore generated benchmark file
* copy the response strings directly into benchmark, so older versions
  don't need to load the test yaml at all (they may not be able to).

Author: nevans

.gitignore

@@ -8,4 +8,5 @@
 /spec/reports/
 /tmp/
 /Gemfile.lock
-benchmarks/Gemfile*
+/benchmarks/Gemfile*
+/benchmarks/parser.yml