Remove TODO in libcudf_kafka recipe (#10309)

From my local testing, it seems that the `librdkafka` `run_exports` is now fixed, so this line can be safely removed.

Authors:
  - AJ Schmidt (https://github.com/ajschmidt8)

Approvers:
  - Jordan Jacobelli (https://github.com/Ethyling)

URL: #10309

conda/recipes/libcudf_kafka/meta.yaml

@@ -27,8 +27,6 @@ requirements:
   host:
     - libcudf {{version}}
     - librdkafka >=1.7.0,<1.8.0a0
-  run:
-    - {{ pin_compatible('librdkafka', max_pin='x.x') }} #TODO: librdkafka should be automatically included here by run_exports but is not
 
 test:
   commands: