MINOR: Adjust test params pursuant to KAFKA-4514. (#5777)
MINOR: Adjust test params pursuant to KAFKA-4514. (#5777)

PR #2267 Introduced support for Zstandard compression. The relevant test expects values for `num_nodes` and `num_producers` based on the (now-incremented) count of compression types.

Passed the affected, previously-failing test:
`ducker-ak test tests/kafkatest/tests/client/compression_test.py`

Reviewers: Jason Gustafson <68c46a606457643eab92053c1c05574abb26f861@confluent.io>
gf53520/kafka,lindong28/kafka,TiVo/kafka,KevinLiLu/kafka,noslowerdna/kafka,noslowerdna/kafka,apache/kafka,noslowerdna/kafka,gf53520/kafka,apache/kafka,lindong28/kafka,guozhangwang/kafka,apache/kafka,guozhangwang/kafka,Chasego/kafka,lindong28/kafka,lindong28/kafka,KevinLiLu/kafka,TiVo/kafka,noslowerdna/kafka,guozhangwang/kafka,KevinLiLu/kafka,Chasego/kafka,gf53520/kafka,sslavic/kafka,KevinLiLu/kafka,apache/kafka,Chasego/kafka,Chasego/kafka,sslavic/kafka,TiVo/kafka,guozhangwang/kafka,sslavic/kafka,TiVo/kafka,gf53520/kafka,sslavic/kafka