AI.DAGRUN / AI.DAGRUN_RO negative tests inconsistent state

[filipecosta90]

This issue came around when I was checking the redisai-js CI:
https://app.circleci.com/pipelines/github/RedisAI/redisai-js/357/workflows/2fe83c67-79de-4ed2-aa59-2151271e4963/jobs/343

using the edge image 247c4e5 we can see that a negative aidagrun /ai.dagrun_ro leaves the client in an inconsistent state ( even on the following commands -- check inf modules reply... ).

127.0.0.1:6379> "AI.DAGRUN" "|>" "AI.MODELRUN" "dont-exist" "INPUTS" "tensorA" "OUTPUTS" "tensorC"
(error) ERR model key is empty
127.0.0.1:6379> "AI.DAGRUN" "|>" "AI.MODELRUN" "dont-exist" "INPUTS" "tensorA" "OUTPUTS" "tensorC"
(error) ERR Model not found
127.0.0.1:6379> "AI.DAGRUN" "|>" "AI.MODELRUN" "dont-exist" "INPUTS" "tensorA" "OUTPUTS" "tensorC"
(error) ERR model key is empty
127.0.0.1:6379> "AI.DAGRUN" "|>" "AI.MODELRUN" "dont-exist" "INPUTS" "tensorA" "OUTPUTS" "tensorC"
(error) ERR Model not found
127.0.0.1:6379> info modules
ERR model key is empty