[lldb][test] Re-enable swift stepping on linux

rdar://77785062
(cherry picked from commit 2361da5)

Author: da-viper

lldb/test/API/lang/swift/stepping/TestSwiftStepping.py

@@ -25,7 +25,6 @@ class TestSwiftStepping(lldbtest.TestBase):
     mydir = lldbtest.TestBase.compute_mydir(__file__)
 
     @swiftTest
-    @skipIfLinux
     def test_swift_stepping(self):
         """Tests that we can step reliably in swift code."""
         self.build()