Add initial Microsoft Teams support

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

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

@@ -0,0 +1,15 @@
+// Code generated by msgraph-generate.go DO NOT EDIT.
+
+package msgraph
+
+// ProtectGroup undocumented
+type ProtectGroup struct {
+	// LabelActionBase is the base model of ProtectGroup
+	LabelActionBase
+	// AllowEmailFromGuestUsers undocumented
+	AllowEmailFromGuestUsers *bool `json:"allowEmailFromGuestUsers,omitempty"`
+	// AllowGuestUsers undocumented
+	AllowGuestUsers *bool `json:"allowGuestUsers,omitempty"`
+	// Privacy undocumented
+	Privacy *GroupPrivacy `json:"privacy,omitempty"`
+}