This commit introduces the OpenTelementryAttributes class that fetches
OTEL_RESOURCE_ATTRIBUTES and OTEL_SERVICE_NAME environment variables
and merges it with user-defined resource attributes.
Besides that, this commit includes spec-compliant proper handling of
OTEL_RESOURCE_ATTRIBUTES in OtlpMetricsPropertiesConfigAdapter and
OpenTelemetryAutoConfiguration.
See gh-44394
Signed-off-by: Dmytro Nosan <dimanosan@gmail.com>
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