Remove impressions pixels from Markdown files (Azure#39893)

Author: scottaddie

sdk/eventhub/azure-eventhub-checkpointstoreblob-aio/CHANGELOG.md

@@ -71,5 +71,3 @@ This release has trivial internal changes only. No feature changes.
 **New features**
 
 - `BlobPartitionManager` that uses Azure Blob Storage Block Blob to store EventProcessor checkpoint data
-
-![Impressions](https://azure-sdk-impressions.azurewebsites.net/api/impressions/azure-sdk-for-python/sdk/eventhub/azure-eventhub-checkpointstoreblob-aio/HISTORY.png)

sdk/eventhub/azure-eventhub-checkpointstoreblob/CHANGELOG.md

@@ -62,5 +62,3 @@ Stable release. No new features or API changes.
 **New features**
 
 - `BlobPartitionManager` that uses Azure Blob Storage Block Blob to store EventProcessor checkpoint data
-
-![Impressions](https://azure-sdk-impressions.azurewebsites.net/api/impressions/azure-sdk-for-python/sdk/eventhub/azure-eventhub-checkpointstoreblob/HISTORY.png)

sdk/identity/azure-identity/migration_guide.md

@@ -121,5 +121,3 @@ The global documentation for authenticating Python apps on Azure is available [h
 [client_secret_cred]: https://aka.ms/azsdk/python/identity/docs#azure.identity.ClientSecretCredential
 [get_client_from_cli_profile]: https://learn.microsoft.com/python/api/azure-common/azure.common.client_factory?view=azure-python#get-client-from-cli-profile-client-class----kwargs-
 [json]: https://docs.python.org/3/library/json.html#json.load
-
-![Impressions](https://azure-sdk-impressions.azurewebsites.net/api/impressions/azure-sdk-for-python%2Fsdk%2Fidentity%2Fazure-identity%2Fmigration_guide.png)