renamed License.txt to THIRD-PARTH-NOTICE.txt file with addition of a header per https://github.com/dotnet/runtime/blob/main/docs/project/copyright.md

Author: Tanya-Solyanik

src/System.Windows.Forms/tests/IntegrationTests/DesignSurface/LICENSE.txt renamed to src/System.Windows.Forms/tests/IntegrationTests/DesignSurface/THIRD-PARTY-NOTICE.txt

@@ -1,3 +1,17 @@
+.NET uses third-party libraries or other resources that may be
+distributed under licenses different than the .NET software.
+
+In the event that we accidentally failed to list a required notice, please
+bring it to our attention. Post an issue or email us:
+
+           [email protected]
+
+The attached notice is provided for information only.
+
+
+License notice for Tiny Form Designer and DesignSurface (Extended)
+--------------------------------------------------------------------------
+
 The Code Project Open License (CPOL) 1.02
 
 Preamble