inncorrect "available VM extentisions image list"

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Find the available VM extensions for a subscription and region.
⇒There were so many extensions listed that it was difficult to determine which extensions were available. Some private extensions are also included in the list. The description of "available" VM extensions list is incorrect.

forexample the bellow.

AzureDiagnosticsLinuxExtIaaS7.Test / Microsoft.OSTCExtensions.Test
LinuxSLES15 / Microsoft.Azure.SiteRecovery2.Test

...etc.

---
#### Document Details

⚠ *Do not edit this section. It is required for learn.microsoft.com ➟ GitHub issue linking.*

* ID: 75b43753-55c6-9a97-79e7-cb102ca16905
* Version Independent ID: b88b763f-9855-5a37-ab97-375e7438f8c9
* Content: [az vm extension image](https://learn.microsoft.com/en-us/cli/azure/vm/extension/image?view=azure-cli-latest)
* Content Source: [latest/docs-ref-autogen/vm/extension/image.yml](https://github.com/MicrosoftDocs/azure-docs-cli/blob/main/latest/docs-ref-autogen/vm/extension/image.yml)
* Service: **virtual-machines**
* GitHub Login: @rloutlaw
* Microsoft Alias: **routlaw**