[lldb-dap] Re-enable test cases on Darwin

Summary:
Looks like some test cases should be re-enabled in 0b8dfb5
But only comments was removed. The skip statements survived the change.

Test Plan:
./bin/llvm-lit -va /Users/wanyi/llvm-upstream/llvm-project/lldb/test/API/tools/lldb-dap/attach/TestDAP_attach.py
All tests passed locally on my mac

Author: kusmour

lldb/test/API/tools/lldb-dap/attach/TestDAP_attach.py

@@ -93,7 +93,6 @@ def cleanup():
         self.set_and_hit_breakpoint(continueToExit=True)
 
     @skipUnlessDarwin
-    @skipIfDarwin
     @skipIfNetBSD  # Hangs on NetBSD as well
     def test_by_name_waitFor(self):
         """
@@ -114,7 +113,6 @@ def test_by_name_waitFor(self):
         self.attach(program=program, waitFor=True)
         self.set_and_hit_breakpoint(continueToExit=True)
 
-    @skipIfDarwin
     @skipIfNetBSD  # Hangs on NetBSD as well
     def test_commands(self):
         """
@@ -201,7 +199,6 @@ def test_commands(self):
         self.verify_commands("exitCommands", output, exitCommands)
         self.verify_commands("terminateCommands", output, terminateCommands)
 
-    @skipIfDarwin
     @skipIfNetBSD  # Hangs on NetBSD as well
     @skipIf(
         archs=["arm", "aarch64"]