Fix typo in DBDataPermission.xml (dotnet#7853)

In Clear method definition, correct typo "previous" to "previously".

Author: Nicholas Piazza

xml/System.Data.Common/DBDataPermission.xml

@@ -376,7 +376,7 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>Removes all permissions that were previous added using the <see cref="M:System.Data.Common.DBDataPermission.Add(System.String,System.String,System.Data.KeyRestrictionBehavior)" /> method.</summary>
+        <summary>Removes all permissions that were previously added using the <see cref="M:System.Data.Common.DBDataPermission.Add(System.String,System.String,System.Data.KeyRestrictionBehavior)" /> method.</summary>
         <remarks>To be added.</remarks>
         <related type="Article" href="/dotnet/framework/data/adonet/ado-net-overview">ADO.NET Overview</related>
       </Docs>