[@azure/eventgrid-namespaces][@azure/eventgrid]Migrate EventGrid Packages away from Local Authentication

[sarangan12]

Packages impacted by this PR

1. @azure/eventgrid-namespaces
2. @azure/eventgrid

Issues associated with this PR

#29699

Describe the problem that is addressed by this PR

This PR has been created to move the eventgrid packages away from Local Authentication. The migration guide has been used for reference.

What are the possible designs available to address the problem? If there are more than one possible design, why was the one in this PR chosen?

No special design consideration.

Are there test cases added in this PR? (If not, why?)

NA. Existing test cases are sufficient.

Provide a list of related PRs (if any)

1. [Test Migration] Test Suites To Be Migrated #29699
2. [@azure/monitor-query][@azure/monitor-ingestion] Migrate Monitor Packages away from Local Authentication #30209

Command used to generate this PR:**(Applicable only to SDK release request PRs)

Checklists

• Added impacted package name to the issue description
• Does this PR needs any fixes in the SDK Generator?** (If so, create an Issue in the Autorest/typescript repository and link it here)
• Added a changelog (if necessary)

[azure-sdk]

API change check

API changes are not detected in this pull request.

[minhanh-phan]