Update hdinsight-release-notes.md

Removed known issue about Jupyter Notebook issue as it has been fixed.

Author: mimig1

articles/hdinsight/hdinsight-release-notes.md

@@ -7,7 +7,7 @@ ms.reviewer: jasonh
 ms.custom: hdinsightactive
 ms.service: hdinsight
 ms.topic: conceptual
-ms.date: 01/29/2020
+ms.date: 03/13/2020
 ---
 # Release notes
 
@@ -60,38 +60,3 @@ HDInsight continues to make cluster reliability and performance improvements.
 
 ## Component version change
 No component version change for this release. You could find the current component versions for HDInsight 4.0 ad HDInsight 3.6 here.
-
-## Known issues
-
-As of January 29, 2020, there is an active issue in which you may receive an error when attempting to use a Jupyter notebook. Use the steps below to fix the issue. You can also refer to this [MSDN post](https://social.msdn.microsoft.com/Forums/en-us/8c763fb4-79a9-496f-a75c-44a125e934ac/hdinshight-create-not-create-jupyter-notebook?forum=hdinsight) or this [StackOverflow post](https://stackoverflow.com/questions/59687614/azure-hdinsight-jupyter-notebook-not-working/59831103) for up-to-date information, or to ask additional questions. This page will be updated when the issue is fixed.
-
-**Errors**
-
-* ValueError: Cannot convert notebook to v5 because that version doesn't exist
-* Error loading notebook An unknown error occurred while loading this notebook. This version can load notebook formats v4 or earlier
-
-**Cause** 
-
-The _version.py file on the cluster was updated to 5.x.x instead of 4.4.x.## or Ambari needs to be restarted.
-
-**Solution**
-
-If you create a new Jupyter notebook and receive one of the errors listed above, perform the following steps to fix the issue.
-
-1. Open Ambari in a web browser by going to `https://CLUSTERNAME.azurehdinsight.net`, where CLUSTERNAME is the name of your cluster.
-1. In Ambari, on the left menu, click **Jupyter**, then on **Service Actions**, click **Stop**.
-1. ssh into the cluster headnode where the Jupyter service is running.
-1. Open the following file /usr/bin/anaconda/lib/python2.7/site-packages/nbformat/_version.py in sudo mode.
-1. Check the value of version_info.
-1. If the value of version_info is set to: 
-
-    version_info = (5, 0, 3)
-
-    Then modify the entry to: 
-    
-    version_info = (4, 4, 0)
-
-    And save the file. 
-
-    If version_info is already set to (4, 4, 0), then continue to the next step as only Ambari needs to be restarted, no additional changes are needed.
-1. Go back to Ambari, and in **Service Actions**, click **Restart All**.