[client] add new module `go.opentelemetry.io/collector/client`

[atoulme]

Description: Create a new go module go.opentelemetry.io/collector/client

Link to tracking Issue: Fixes #9804

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 92.39%. Comparing base (21c3f36) to head (f55ac06).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #9805   +/-   ##
=======================================
  Coverage   92.39%   92.39%           
=======================================
  Files         403      403           
  Lines       18739    18739           
=======================================
  Hits        17313    17313           
  Misses       1066     1066           
  Partials      360      360           

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[bogdandrutu]

Please consider a big refactor (including renaming probably) for this package before marking stable.

[atoulme]

Thanks Bogdan, captured this feedback in https://github.com/open-telemetry/opentelemetry-collector/issues/9818

[github-actions[bot]]

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

[atoulme]

There might be a few other ways to go about this ; closing for now this PR and let's maybe work on a refactoring approach.

[github-actions[bot]]

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

[github-actions[bot]]

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

[mx-psi]

@atoulme can you fix the merge conflict?

@open-telemetry/collector-approvers I will merge this on Friday if nobody blocks before then