Remove test for -fcoroutines-ts

After clang update, we got the below error:
  external/libcxx/libcxx_test_template.cpp
  clang++: error: unknown argument: '-fcoroutines-ts'

Since this option has been removed in clang, remove test for it.

Bug: 280683256
Test: build with clang-r498229
Change-Id: Icecd7152f8d724d680bf17e3f920f15365b285a6

Android.bp

@@ -251,8 +251,6 @@ cc_binary {
     cppflags: [
         "-fsized-deallocation",
         "-fexceptions",
-        "-fcoroutines-ts",
-        "-Wno-deprecated-experimental-coroutine",
         "-Wno-format-zero-length",
         "-Wno-implicit-fallthrough",
         "-Wno-non-virtual-dtor",

utils/libcxx/android/test/config.py

@@ -107,7 +107,6 @@ class Configuration(libcxx.test.config.Configuration):
         self.config.available_features.add('c++experimental')
         self.config.available_features.add('c++fs')
         self.config.available_features.add('c++filesystem')
-        self.config.available_features.add('fcoroutines-ts')
         std_pattern = re.compile(r'-std=(c\+\+\d[0-9x-z])')
         match = std_pattern.search(self.cxx.cxx_template)
         if match: