[repo] Add THIRD-PARTY-NOTICES file (#5190)

OpenTelemetry.sln

@@ -19,6 +19,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution
 		NuGet.config = NuGet.config
 		OpenTelemetry.proj = OpenTelemetry.proj
 		README.md = README.md
+		THIRD-PARTY-NOTICES = THIRD-PARTY-NOTICES
 		VERSIONING.md = VERSIONING.md
 	EndProjectSection
 EndProject

THIRD-PARTY-NOTICES

@@ -0,0 +1,31 @@
+OpenTelemetry .NET uses third-party libraries or other resources that may be
+distributed under licenses different than the OpenTelemetry .NET software.
+
+The attached notices are provided for information only.
+
+License notice for .NET
+-------------------------------
+
+The MIT License (MIT)
+
+Copyright (c) .NET Foundation and Contributors
+
+All rights reserved.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.