Fix Fsharp template

[TheAngryByrd]

Fixed issues I had while testing the F# template

[TheAngryByrd]

Added specific comments to why changes were made

[CodeTherapist]

Thanks for your work 👍 I appreciate always contributions to my work - since it's a great way to learn!
I would like to understand why my dotnet build command was successful. Could you please ellaborate why that could be and which version do you use of Visual Studio / msbuild / dotnet sdk?

[TheAngryByrd]

So dotnet build would have been successful but you would have has issues running benchmark since no files were listed in the fsproj. Unfortunately there's no good official docs on this subject but the gist of it is fsproj files require fs files to be listed as Compile in an ItemGroup. Also if a file references another type or value in another file, (such as the benchmark referencing the config class) that file must be above listed above it in the file order.

For reference dotnet info

dotnet --info
.NET Core SDK (reflecting any global.json):
 Version:   2.2.203
 Commit:    e5bab63eca

Runtime Environment:
 OS Name:     Mac OS X
 OS Version:  10.14
 OS Platform: Darwin
 RID:         osx.10.14-x64
 Base Path:   /usr/local/share/dotnet/sdk/2.2.203/

Host (useful for support):
  Version: 2.2.5
  Commit:  0a3c9209c0

[TheAngryByrd]

Without the files in the fsproj:

$ dotnet benchmark ./bin/Release/netstandard2.0/benchmark-template-test.dll
No benchmarks to choose from. Make sure you provided public non-sealed non-static types with public [Benchmark] methods.

With the files in the fsproj:

$ dotnet benchmark ./bin/Release/netstandard2.0/benchmark-template-test.dll

Available Benchmark:
  #0 MyBenchmark


You should select the target benchmark(s). Please, print a number of a benchmark (e.g. '0') or a contained benchmark caption (e.g. 'MyBenchmark'):
If you want to select few, please separate them with space ` ` (e.g. `1 2 3`)
You can also provide the class name in console arguments by using --filter. (e.g. '--filter *MyBenchmark*'):