After node-config was bumped to 3.3.9 (from 3.3.6), it started throwing errors if
configurations are mutated without the ALLOW_CONFIG_MUTATIONS env var set.
We mutate some configs directly, but I every time I added one of those I made sure that
they are always deep cloned.
However, we hit an issue with kurento-client mutating a config input, which is an indirect mutation.
So, to prevent further surprises I'm allowing mutations on production while prohibiting them in dev
envs until I'm 100% sure nothing, direct on indirect, improperly mutates configuration values.
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