ML.NET clustering tutorial: updated to 1.0 (#868)

Author: pkulikov

machine-learning/tutorials/IrisFlowerClustering/IrisFlowerClustering.csproj

@@ -10,7 +10,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.ML" Version="1.0.0-preview" />
+    <PackageReference Include="Microsoft.ML" Version="1.0.0" />
   </ItemGroup>
 
   <ItemGroup>