[lldb][test] Remove expected failure marker for TestPlatformAttach on windows (#68193)

Looks like this test passes since #68050.

Author: antmox

lldb/test/API/functionalities/gdb_remote_client/TestPlatformAttach.py

@@ -7,7 +7,6 @@
 
 class TestPlatformAttach(GDBRemoteTestBase):
     @skipIfRemote
-    @expectedFailureAll(oslist=["windows"], bugnumber="llvm.org/pr52451")
     def test_attach(self):
         """Test attaching by name"""