Plugin groups (#30320)

* add new pluginapi methods

* SAML login hook

* set ReAddRemovedMembers to true for plugin groups

* change to DoLogin signature for SAML

server/public/plugin/plugintest/hooks.go

@@ -13,6 +13,8 @@ import (
 	model "github.com/mattermost/mattermost/server/public/model"
 
 	plugin "github.com/mattermost/mattermost/server/public/plugin"
+
+	saml2 "github.com/mattermost/gosaml2"
 )
 
 // Hooks is an autogenerated mock type for the Hooks type
@@ -384,6 +386,24 @@ func (_m *Hooks) OnPluginClusterEvent(c *plugin.Context, ev model.PluginClusterE
 	_m.Called(c, ev)
 }
 
+// OnSAMLLogin provides a mock function with given fields: c, user, assertion
+func (_m *Hooks) OnSAMLLogin(c *plugin.Context, user *model.User, assertion *saml2.AssertionInfo) error {
+	ret := _m.Called(c, user, assertion)
+
+	if len(ret) == 0 {
+		panic("no return value specified for OnSAMLLogin")
+	}
+
+	var r0 error
+	if rf, ok := ret.Get(0).(func(*plugin.Context, *model.User, *saml2.AssertionInfo) error); ok {
+		r0 = rf(c, user, assertion)
+	} else {
+		r0 = ret.Error(0)
+	}
+
+	return r0
+}
+
 // OnSendDailyTelemetry provides a mock function with given fields:
 func (_m *Hooks) OnSendDailyTelemetry() {
 	_m.Called()