[LogAnalytics] Fix broken link
This package is no longer being maintained. Use the [azure-monitor-query](https://pypi.org/project/azure-monitor-query/) package instead.
-For migration instructions, see the [migration guide](https://azsdk/python/migrate/la-to-monitor-query).
+For migration instructions, see the [migration guide](https://aka.ms/azsdk/python/migrate/la-to-monitor-query).
![image](https://azure-sdk-impressions.azurewebsites.net/api/impressions/azure-sdk-for-python%2Fazure-loganalytics%2FREADME.png)
