ServiceBus2018-preview: Updated as per review comments from ARM Team for Eventhub swagger

[v-Ajnava]

Latest improvements:

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[openapi-portal-comment]

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[AutorestCI]

Automation for azure-sdk-for-python

Nothing to generate for azure-sdk-for-python

[v-Ajnava]

EventHub: PR link with ARM team comments : #4748

[AutorestCI]

Automation for azure-sdk-for-js

The initial PR has been merged into your service PR:
Azure/azure-sdk-for-js#765

[azuresdkci]

Can one of the admins verify this patch?

[AutorestCI]

Automation for azure-sdk-for-ruby

A PR has been created for you:
Azure/azure-sdk-for-ruby#2122

[AutorestCI]

Automation for azure-sdk-for-go

Nothing to generate for azure-sdk-for-go

[AutorestCI]

Automation for azure-sdk-for-node

The initial PR has been merged into your service PR:
Azure/azure-sdk-for-node#4530

[AutorestCI]

Automation for azure-sdk-for-java

Nothing to generate for azure-sdk-for-java

[anuchandy]

Closing and re-opening to rerun diff tool, which was failing with message

 An assembly specified in the application dependencies manifest (OpenApiDiff.deps.json) was not found

[openapi-portal-comment]

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[anuchandy]

@sarangan12 investigated the CI OpenAPIDiff invocation failure. This is happening for 3 PRs, images used to run tools for those PR were invalid, this fixed now.