Revert "XFAIL test under Linux"

This reverts commit f4e1af0.

Author: adrian-prantl

lldb/test/API/lang/swift/dwarfimporter/BridgingPCH/TestSwiftDWARFImporterBridgingPCH.py

@@ -41,7 +41,6 @@ def build(self):
     @skipIf(oslist=['windows'])
     # We delete the pch that would contains the debug info as part of the setup.
     #@skipIf(debug_info=no_match(["dsym"]))
-    @expectedFailureAll(oslist=['linux'], bugnumber='rdar://104670979')
     @swiftTest
     def test_dwarf_importer(self):
         lldb.SBDebugger.MemoryPressureDetected()