Add documentation example for exporter package (#5675)

[heitorganzeli]

Description

This PR introduces a testable example to the package exporter. it's a similar example to the documentation one on https://opentelemetry.io/docs/collector/building/receiver/#designing-and-validating-receiver-settings

Issue: #5675 (comment)

Testing

the testable example was executed successfully

Documentation

this testable example follows https://go.dev/blog/examples#larger-examples format and should be automatically added to exporter package documentation

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.69%. Comparing base (727ae96) to head (f93bd00).

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #12958   +/-   ##
=======================================
  Coverage   91.69%   91.69%           
=======================================
  Files         503      503           
  Lines       27555    27555           
=======================================
  Hits        25267    25267           
  Misses       1808     1808           
  Partials      480      480           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.