feat(exporter-prometheus): add additional attributes option

[marius-a-mueller]

Which problem is this PR solving?

At the moment there is no way to set default/static attributes for all metrics that are being exported by the Prometheus exporter. This PR adds an option for adding resource attributes as metric attributes.

Fixes # (issue)

• #5073

Short description of the changes

• add withResourceConstantLabels option to ExporterConfig
• use regex pattern to choose which resource attributes will be added as metric attributes
• use already implemented logic for additional attributes
• add unit tests

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• unit tests with npm test

Checklist:

• Followed the style guidelines of this project
• Unit tests have been added
• Documentation has been updated

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: marius-a-mueller / name: Marius Müller (a36a818)

[pichlermarc]

I think the way to accomplish this would be to implement this specification: https://github.com/open-telemetry/opentelemetry-specification/blob/01066fe9112ce4dad4371418d88161221bf8db3e/specification/metrics/sdk_exporters/prometheus.md?plain=1#L60-L64

[pichlermarc]

The way the specification suggests to handle this is more closely aligned with OTel concepts and would also solve #5073

[marius-a-mueller]

Okay, I implemented the feature as written in the specification. I just need a bit longer for the CLA authorization.

[marius-a-mueller]

And now I have the CLA authorization too.