[eg] make req/optional more explicit in readme

[l0lawrence]

No description provided.

[openapi-pipeline-app]

Next Steps to Merge

Next steps that must be taken to merge this PR:

• ❌ The required check named SDK azure-sdk-for-go has failed. Refer to the check in the PR's 'Checks' tab for details on how to fix it and consult the aka.ms/ci-fix guide. In addition, refer to step 3 in the PR workflow diagram

[openapi-pipeline-app]

Generated ApiView

Language	Package Name	ApiView Link
.Net	Azure.Messaging.EventGrid.SystemEvents	https://apiview.dev/Assemblies/Review/3e102a891e5445af8be8cde833dbb702?revisionId=43800041ddae45d596068a9e835ebd25
Python	azure-eventgrid	https://apiview.dev/Assemblies/Review/c554ddbabc6e40348998b1656e0ff585?revisionId=a2ce0349845049dba4da74f3aca0cd0e

[azure-sdk]

API change check

APIView has identified API level changes in this PR and created following API reviews.

Microsoft.EventGrid
Microsoft.EventGrid.SystemEvents
AnomalyDetector
Azure.Batch
ContentSafety
Language.Conversations.Authoring
Language.AnalyzeDocuments
Language.Text
Language.Text.Authoring
Language.Conversations
Azure.OpenAI
Microsoft.Speech.VideoTranslation