fix: make criticality attribute opt-in #3340

[thompson-tomo]

Fixes #3340

Changes

This removes the attribute stability exclusion on the service entity which is not relevant since entity was split. What emerged was that the criticality attribute was now conflicting. To resolve criticality is now opt-in but can be promoted at a later point it is stablised.

A changelog has been left out as the attribute is not included in any semconv release as it has just been added.

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