feat(nodejs): drop the trailing comma from OTEL_RESOURCE_ATTRIBUTES

[wpessers]

For the @opentelemetry/core upgrade to 2.6.0 in #2165 there's a breaking change regarding parsing of the OTEL_RESOURCE_ATTRIBUTES and:

Per spec, any parsing error results in ignoring the entire environment variable.

Due to the current code leaving a trailing comma in the $OTEL_RESOURCE_ATTRIBUTES value in the case where the user has it unset or empty, specifically this code in the upstream package would lead to an error being thrown:
https://github.com/open-telemetry/opentelemetry-js/blob/425bbfe4b341de82a07f16086a69787b31e97b9d/packages/opentelemetry-resources/src/detectors/EnvDetector.ts#L76-L92

[herin049]

Honestly, it might be worth submitting a PR to OpenTelemetry Node.js to fix this, since I wouldn't expect trailing commas to be an error. Pretty sure in Python we just ignore anything that parses to pure whitespace after splitting the string.

[wpessers]

Honestly, it might be worth submitting a PR to OpenTelemetry Node.js to fix this, since I wouldn't expect trailing commas to be an error. Pretty sure in Python we just ignore anything that parses to pure whitespace after splitting the string.

Fair point @herin049! I will follow up in the js-contrib on this!