[exporter/awsemf] Add AppSignals metadata flag into user-agent in EMF exporter

[jj22ee]

Description:

Cherry-picking from downstream: amazon-contributing#105

This PR adds AppSignals metadata flag in user-agent in EMF exporter, so CWLogs backend can indicate EMF logs request type for the corresponding actions

Link to tracking Issue:

Testing:
Unit Testing

Documentation:

[bryan-aguilar]

Sorry for dismissing my review after approval. The idea of making the options more generalized came to me a bit later but I think it could be a good way to avoid a tight scope.

Let's take another look at the option scope.

[jj22ee]

In latest commit:

• Replaced WithEnabledAppSignals with WithUserAgentExtras(ex1, ex2, ....)
  • strings provided to WithUserAgentExtras will be added to user agent of the cliennt
• Logic to add "AppSignals" string is now done outside of cwlog_client, now inside emf_exporter

Before this change, cwlog_client will control what strings can get added to the user agent based on flags set by the "WithOption" inputs. Now, there is a "WithOption" input to explicitly add strings to user agent. Pinging @bryan-aguilar

[jj22ee]

Thanks! Can this PR be marked as ready for merge?

[jj22ee]

pinging @jpkrohling @bogdandrutu @bryan-aguilar for merge

[jj22ee]

We will need a different approver/maintainer to help approve/merge this PR, afaik @bryan-aguilar may not be available to do this as of now.

Can you take a look @jpkrohling @bogdandrutu

[jj22ee]

@fatsheep9146 Could you help take a look for approving our PR for merge? We have sufficient reviews from AWS side, and @bryan-aguilar is currently not be available to help continue his review afaik.

[github-actions]

This PR was marked stale due to lack of activity. It will be closed in 14 days.