Correcting default instance name

Line 39 says "If you do not specify an instance, the default instance is used."
Line 49 shows an example where instance is not specified, and it says the instance is "the instance where RegisterRExt is run."
Line 39 is correct, so changing line 49 to match.

Author: garyericson

docs/machine-learning/package-management/r-package-how-to-enable-or-disable.md

@@ -46,7 +46,7 @@ To enable or disable package management on SQL Server, use the command-line util
 
     This command creates some database artifacts, including the following database roles that are used for controlling user permissions: `rpkgs-users`, `rpkgs-private`, and `rpkgs-shared`.
 
-    For example, the following command enables package management on the database, on the instance where RegisterRExt is run. If you do not specify a user, the current security context is used.
+    For example, the following command enables package management on the database, on the default instance. If you do not specify a user, the current security context is used.
 
     `RegisterRExt.exe /install pkgmgmt /database:TestDB`