Update .codecov.yml (#3356)

.codecov.yml

@@ -4,3 +4,10 @@ ignore:
   - "sentinel-benchmark/.*"
   - "sentinel-transport/.*"
   - "sentinel-core/src/main/java/com/alibaba/csp/sentinel/eagleeye/*"
+comment:                  # this is a top-level key
+  layout: " diff, flags, files"
+  behavior: default
+  require_changes: false  # if true: only post the comment if coverage changes
+  require_base: false        # [true :: must have a base report to post]
+  require_head: true       # [true :: must have a head report to post]
+  hide_project_coverage: false # [true :: only show coverage on the git diff]