Avoid out of sync caused by RedisCodec.encodeValue returning null

[bytestreme]

2012-fix-out-of-sync-when-encodeValue-returns-null

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[bytestreme]

relates to https://github.com/lettuce-io/lettuce-core/issues/2180 https://github.com/lettuce-io/lettuce-core/issues/2012

[mp911de]

We do not want to work around API rules to let folks circumvent these in one place and fix these in another place. The wiki is updated now. If you have code that is highly likely to break during serialization, then either provide a more protective RedisCodec variant or perform serialization in your calling code to raise exceptions eagerly.