GH-9635: Add GetUsersByUsernames to plugin API (#9647)

* add GetUsersByUsernames to plugin api

* fix GetUsersByUsernames comment

plugin/plugintest/api.go

@@ -1161,6 +1161,31 @@ func (_m *API) GetUserStatusesByIds(userIds []string) ([]*model.Status, *model.A
 	return r0, r1
 }
 
+// GetUsersByUsernames provides a mock function with given fields: usernames
+func (_m *API) GetUsersByUsernames(usernames []string) ([]*model.User, *model.AppError) {
+	ret := _m.Called(usernames)
+
+	var r0 []*model.User
+	if rf, ok := ret.Get(0).(func([]string) []*model.User); ok {
+		r0 = rf(usernames)
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).([]*model.User)
+		}
+	}
+
+	var r1 *model.AppError
+	if rf, ok := ret.Get(1).(func([]string) *model.AppError); ok {
+		r1 = rf(usernames)
+	} else {
+		if ret.Get(1) != nil {
+			r1 = ret.Get(1).(*model.AppError)
+		}
+	}
+
+	return r0, r1
+}
+
 // GetUsersInTeam provides a mock function with given fields: teamId, page, perPage
 func (_m *API) GetUsersInTeam(teamId string, page int, perPage int) ([]*model.User, *model.AppError) {
 	ret := _m.Called(teamId, page, perPage)