[lldb][test] Skip TestFrameVarDILGlobalVariableLookup.py on older AArch64 macOS version

Currently failing on the arm64 macOS CI with:
```
06:59:37  Traceback (most recent call last):
06:59:37    File "/Users/ec2-user/jenkins/workspace/llvm.org/lldb-cmake-sanitized/llvm-project/lldb/test/API/commands/frame/var-dil/basics/GlobalVariableLookup/TestFrameVarDILGlobalVariableLookup.py", line 47, in test_frame_var
06:59:37      self.expect_var_path("ExtStruct::static_inline", value="16")
06:59:37    File "/Users/ec2-user/jenkins/workspace/llvm.org/lldb-cmake-sanitized/llvm-project/lldb/packages/Python/lldbsuite/test/lldbtest.py", line 2589, in expect_var_path
06:59:37      value_check.check_value(self, eval_result, str(eval_result))
06:59:37    File "/Users/ec2-user/jenkins/workspace/llvm.org/lldb-cmake-sanitized/llvm-project/lldb/packages/Python/lldbsuite/test/lldbtest.py", line 301, in check_value
06:59:37      test_base.assertSuccess(val.GetError())
06:59:37    File "/Users/ec2-user/jenkins/workspace/llvm.org/lldb-cmake-sanitized/llvm-project/lldb/packages/Python/lldbsuite/test/lldbtest.py", line 2597, in assertSuccess
06:59:37      self.fail(self._formatMessage(msg, "'{}' is not success".format(error)))
06:59:37  AssertionError: '<user expression 0>:1:1: use of undeclared identifier 'ExtStruct::static_inline'
06:59:37     1 | ExtStruct::static_inline
06:59:37       | ^' is not success
06:59:37  Config=arm64-/Users/ec2-user/jenkins/workspace/llvm.org/lldb-cmake-sanitized/lldb-build/bin/clang
06:59:37  ----------------------------------------------------------------------
06:59:37  Ran 1 test in 2.322s
06:59:37
```

Can't repro this locally so skipping on older macOS versions that the CI
is running.

Author: Michael137

lldb/test/API/commands/frame/var-dil/basics/GlobalVariableLookup/TestFrameVarDILGlobalVariableLookup.py

@@ -18,6 +18,7 @@ class TestFrameVarDILGlobalVariableLookup(TestBase):
     # each debug info format.
     NO_DEBUG_INFO_TESTCASE = True
 
+    @skipIf(macos_version=["<", "15.0"], archs=["arm64", "arm64e"])
     def test_frame_var(self):
         self.build()
         lldbutil.run_to_source_breakpoint(