StaleLeaderEpochCodeError renamed/removed, error code 13 is NetworkExceptionError

**Describe the bug**
kafka-python has changed/renamed error code 13 from StaleLeaderEpochCodeError to NetworkExceptionError in kafka-python 2.0.4 - https://github.com/dpkp/kafka-python/compare/2.0.3...2.0.4#diff-f5c6e5f20fe82d1a9b3449920cb1f7cf6bbbd448bd516f25c4b414ed2ae20f98. This matches kafka docs for protocol errors - https://kafka.apache.org/11/protocol.html#protocol_error_codes

**Expected behaviour**
aoikafka errors should be updated to match. https://github.com/aio-libs/aiokafka/blob/master/aiokafka/errors.py#L42

**Environment (please complete the following information):**
N/A

**Reproducible example**
N/A