Add initial Microsoft Teams support

Documentation on https://github.com/42wim/matterbridge/wiki/MS-Teams-setup

vendor/github.com/yaegashi/msgraph.go/beta/AppIdentityModel.go

@@ -0,0 +1,17 @@
+// Code generated by msgraph-generate.go DO NOT EDIT.
+
+package msgraph
+
+// AppIdentity undocumented
+type AppIdentity struct {
+	// Object is the base model of AppIdentity
+	Object
+	// AppID undocumented
+	AppID *string `json:"appId,omitempty"`
+	// DisplayName undocumented
+	DisplayName *string `json:"displayName,omitempty"`
+	// ServicePrincipalID undocumented
+	ServicePrincipalID *string `json:"servicePrincipalId,omitempty"`
+	// ServicePrincipalName undocumented
+	ServicePrincipalName *string `json:"servicePrincipalName,omitempty"`
+}