remove unused test linux file

linux/test/polyvox_filament_plugin_test.cc

@@ -1,31 +0,0 @@
-#include <flutter_linux/flutter_linux.h>
-#include <gmock/gmock.h>
-#include <gtest/gtest.h>
-
-#include "include/flutter_filament/flutter_filament_plugin.h"
-#include "flutter_filament_plugin_private.h"
-
-// This demonstrates a simple unit test of the C portion of this plugin's
-// implementation.
-//
-// Once you have built the plugin's example app, you can run these tests
-// from the command line. For instance, for a plugin called my_plugin
-// built for x64 debug, run:
-// $ build/linux/x64/debug/plugins/my_plugin/my_plugin_test
-
-namespace flutter_filament {
-namespace test {
-
-TEST(FlutterFilamentPlugin, GetPlatformVersion) {
-  g_autoptr(FlMethodResponse) response = get_platform_version();
-  ASSERT_NE(response, nullptr);
-  ASSERT_TRUE(FL_IS_METHOD_SUCCESS_RESPONSE(response));
-  FlValue* result = fl_method_success_response_get_result(
-      FL_METHOD_SUCCESS_RESPONSE(response));
-  ASSERT_EQ(fl_value_get_type(result), FL_VALUE_TYPE_STRING);
-  // The full string varies, so just validate that it has the right format.
-  EXPECT_THAT(fl_value_get_string(result), testing::StartsWith("Linux "));
-}
-
-}  // namespace test
-}  // namespace flutter_filament