opentelemetry-sdk: drop NaN measurements at instrument level to prevent aggregation poisoning (#5336)

* fix: drop NaN measurements at instrument level to prevent aggregation poisoning

* fix: rename changelog fragment to match PR number

* inf is added now

* fix: log non-finite value in warning messages

* chore: revert stale sphinx version bump from old merge commit

* test: add integration tests for non-finite measurement dropping

* chore: drop sphinx downgrade artifact from stale merge

* fix: rename variable m to metric to satisfy pylint naming rules