Add setting to OAuth handlers to skip local 2FA authentication (#16594)

This PR adds a setting to OAuth and OpenID login sources to allow the source to
skip local 2FA authentication.

Fix #13939

Signed-off-by: Andrew Thornton <art27@cantab.net>

services/forms/auth_form.go

@@ -66,6 +66,7 @@ type AuthenticationForm struct {
 	Oauth2EmailURL                string
 	Oauth2IconURL                 string
 	Oauth2Tenant                  string
+	SkipLocalTwoFA                bool
 	SSPIAutoCreateUsers           bool
 	SSPIAutoActivateUsers         bool
 	SSPIStripDomainNames          bool