Update .htmltest.yml

Author: chalin

.htmltest.yml

@@ -10,6 +10,8 @@ IgnoreDirs:
   # DO NOT EDIT! IgnoreDirs list is auto-generated from markdown file front matter.
   # Ignore blog index pages for all locales and in all blog sections (top-level and years)
   - ^(../)?blog/(\d+/)?page/\d+
+  # Ignore old blog posts
+  - ^(../)?blog/20(19|21|22|23)/
   # TODO drop next lines after https://github.com/open-telemetry/opentelemetry.io/issues/5555 is fixed for these pages:
   - ^zh/docs/concepts/signals/baggage/
   - ^zh/docs/zero-code/php/