Update changelog for 1.13.13

Author: rmosolgo

CHANGELOG.md

@@ -122,6 +122,14 @@
 - __None, ideally.__ If you have an application that ran without warnings on v1.13, you should be able to update to 2.0.0 without a hitch. If this isn't the case, please [open an issue](https://github.com/rmosolgo/graphql-ruby/issues/new?template=bug_report.md&title=[2.0%20update]%20describe%20your%20problem) and let me know what happened! I plan to maintain 1.13 for a while in order to ensure a smooth transition.
 - But, many legacy code components were removed, so if there are any more references to those, there will be name errors! See #3729 for a list of removed components.
 
+# 1.13.13 (31 May 2022)
+
+### New features
+
+- Datadog: update tracer for ddtrace 1.0 #4038
+- Datadog: Add `#prepare_span` hook for custom tags #4067
+- Tracing: Add `OpenTelementry` tracing #4077
+
 # 1.13.12 (14 April 2022)
 
 - Pass `context[:dataloader]` to multiplex context #4026