fix ADR paths in SQL2019 notebooks

Update the filenames for links to the sqlworkshops ADR notebooks

Author: DaveDustin

samples/features/sql2019notebooks/README.md

@@ -18,8 +18,8 @@ The [What's New](https://docs.microsoft.com/en-us/sql/sql-server/what-s-new-in-s
 * **[MemoryOptmizedTempDBMetadata-Python.ipynb](https://github.com/microsoft/sql-server-samples/blob/master/samples/features/in-memory-database/memory-optimized-tempdb-metadata/MemoryOptmizedTempDBMetadata-Python.ipynb)** - This is a Python notebook which shows the benefits of Memory Optimized Tempdb metadata.
 
 ### Availability
-* **[ADR.ipynb](https://github.com/microsoft/sqlworkshops/blob/master/sql2019workshop/sql2019wks/04_Availability/adr/adr.ipynb)** - In this notebook, you will see how fast rollback can now be with Accelerated Database Recovery. You will also see that a long active transaction does not affect the ability to truncate the transaction log.
-* **[ADR_Recovery.ipynb](https://github.com/microsoft/sqlworkshops/blob/master/sql2019workshop/sql2019wks/04_Availability/adr/adr_recovery.ipynb)** - In this example, you will see how Accelerated Database Recovery will speed up recovery.
+* **[Basic_ADR.ipynb](https://github.com/microsoft/sqlworkshops/blob/master/sql2019workshop/sql2019wks/04_Availability/adr/basic_adr.ipynb)** - In this notebook, you will see how fast rollback can now be with Accelerated Database Recovery. You will also see that a long active transaction does not affect the ability to truncate the transaction log.
+* **[Recovery_ADR.ipynb](https://github.com/microsoft/sqlworkshops/blob/master/sql2019workshop/sql2019wks/04_Availability/adr/recovery_adr.ipynb)** - In this example, you will see how Accelerated Database Recovery will speed up recovery.