Remove __v1_type tag when forwarding metrics to otel collector

[acrmp]

Description

• Metrics that were received initially as v1 metrics include a __v1_type tag to indicate the type of v1 metric that was emitted.
• This causes issues for the prometheus exporter as: 'Label names beginning with __ (two "_") are reserved for internal use.' https://prometheus.io/docs/concepts/data_model/
• Remove the __v1_type tag during the conversion so that these metrics will be acceptable to prometheus exporters.

Fixes:

 "__v1_type" is not a valid label name for metric

Type of change

• 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

Testing performed?

• Unit tests
• Integration tests
• Acceptance tests

Checklist:

• This PR is being made against the main branch, or relevant version branch
• I have made corresponding changes to the documentation
• I have added testing for my changes

If you have any questions, or want to get attention for a PR or issue please reach out on the #logging-and-metrics channel in the cloudfoundry slack