Follow up fixes to adding Meter Tag support

[cijothomas]

https://github.com/open-telemetry/opentelemetry-dotnet/pull/5089

https://github.com/open-telemetry/opentelemetry-dotnet/pull/5089#discussion_r1408254794 https://github.com/open-telemetry/opentelemetry-dotnet/pull/5089#discussion_r1408263199 https://github.com/open-telemetry/opentelemetry-dotnet/pull/5089#discussion_r1408473602 - doc follow up

[github-actions[bot]]

This issue was marked stale due to lack of activity and will be closed in 7 days. Commenting will instruct the bot to automatically remove the label. This bot runs once per day.

[TimothyMothra]

• Documentation follow up is still outstanding.
• Need to review if the Prometheus Exporter was ever updated to support Meter Tags.

[cijothomas]

https://github.com/open-telemetry/opentelemetry-dotnet/issues/5859 Needs to be done for this.

[martincostello]

#5859 has been completed.