Multi Tenant sample for Web App calling Web API

[Shama-K]

Purpose

Added sample to demonstrate multi-tenancy in the scenario where Web App calls Web API.

Does this introduce a breaking change?

[ ] Yes
[ x] No

Pull Request Type

What kind of change does this Pull Request introduce?

[ ] Bugfix
[x ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:

How to Test

Use manual steps or app creation scripts to configure the sample, and run the sample.
Test the code.

[derisen]

Good work Shama, LGTM! Few comments:

1. If KnownClientApplication is required, there should be steps in "Registration"
2. I suggest setting TenantID: common (or organizations) as default in appsettings.json files since the sample is multitenant.
3. Double check to confirm if Implicit Flow: ID Token is needed in Web API Registration steps
4. In Prerequisites, I suggest removing trivial items like "internet connection", "windows machine" etc.

[idg-sam]

Runs great from within Windows!

1. Instructions for running from Linux or WSL
2. There was some certificate errors when I tried to run from WSL

[TiagoBrenck]

LGTM, thanks @Shama-K

[MisinformedDNA]

Thanks! This repo is very helpful.