Update to release version of dbup-core 6.0

Author: droyad

src/dbup-mysql/dbup-mysql.csproj

@@ -23,7 +23,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="dbup-core" Version="6.0.0-beta.146"/>
+    <PackageReference Include="dbup-core" Version="6.0.3"/>
     <PackageReference Include="MySqlConnector" Version="2.3.5"/>
   </ItemGroup>