Wrap net35 app in a solution

To see if this is a simple repro of #1213.

Author: rainersigwald

tests/Microsoft.DotNet.Framework.Docker.Tests/projects/dotnetapp-3.5/Dockerfile

@@ -5,7 +5,7 @@ ARG BASE_RUNTIME_IMAGE
 FROM $BASE_BUILD_IMAGE as builder
 WORKDIR /app
 COPY . ./
-RUN ["msbuild.exe", "dotnetapp-3.5.csproj", "/p:Configuration=Release"]
+RUN ["msbuild.exe", "dotnetapp-3.5.sln", "/p:Configuration=Release"]
 
 
 FROM $BASE_RUNTIME_IMAGE

tests/Microsoft.DotNet.Framework.Docker.Tests/projects/dotnetapp-3.5/dotnetapp-3.5.sln

@@ -0,0 +1,34 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.0.31903.59
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "dotnetapp-3.5", "dotnetapp-3.5.csproj", "{E00527DF-512D-47B6-B341-C090F0D01DA7}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Debug|x64 = Debug|x64
+		Debug|x86 = Debug|x86
+		Release|Any CPU = Release|Any CPU
+		Release|x64 = Release|x64
+		Release|x86 = Release|x86
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{E00527DF-512D-47B6-B341-C090F0D01DA7}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{E00527DF-512D-47B6-B341-C090F0D01DA7}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{E00527DF-512D-47B6-B341-C090F0D01DA7}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{E00527DF-512D-47B6-B341-C090F0D01DA7}.Debug|x64.Build.0 = Debug|Any CPU
+		{E00527DF-512D-47B6-B341-C090F0D01DA7}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{E00527DF-512D-47B6-B341-C090F0D01DA7}.Debug|x86.Build.0 = Debug|Any CPU
+		{E00527DF-512D-47B6-B341-C090F0D01DA7}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{E00527DF-512D-47B6-B341-C090F0D01DA7}.Release|Any CPU.Build.0 = Release|Any CPU
+		{E00527DF-512D-47B6-B341-C090F0D01DA7}.Release|x64.ActiveCfg = Release|Any CPU
+		{E00527DF-512D-47B6-B341-C090F0D01DA7}.Release|x64.Build.0 = Release|Any CPU
+		{E00527DF-512D-47B6-B341-C090F0D01DA7}.Release|x86.ActiveCfg = Release|Any CPU
+		{E00527DF-512D-47B6-B341-C090F0D01DA7}.Release|x86.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+EndGlobal