Skip lldb tests in Swift smoke test preset

[shahmishal]

Skipping LLDB test suite due to failing tests, which is blocking PR testing.

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Issue Details
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FAIL: test_fp_register_write_dwarf (functionalities/register/register_command/TestRegisters.py)
FAIL: test_fp_register_write_dwo (functionalities/register/register_command/TestRegisters.py)
FAIL: test_fp_register_write_gmodules (functionalities/register/register_command/TestRegisters.py)
FAIL: test_fp_special_purpose_register_read_dwarf (functionalities/register/register_command/TestRegisters.py)
FAIL: test_fp_special_purpose_register_read_dwo (functionalities/register/register_command/TestRegisters.py)
FAIL: test_fp_special_purpose_register_read_gmodules (functionalities/register/register_command/TestRegisters.py)
FAIL: test_grp_register_save_restore_works_no_suffix_llgs (tools/lldb-server/TestGdbRemoteRegisterState.py)
FAIL: test_grp_register_save_restore_works_with_suffix_llgs (tools/lldb-server/TestGdbRemoteRegisterState.py)
FAIL: test_p_returns_correct_data_size_for_each_qRegisterInfo_attach_llgs (tools/lldb-server/TestLldbGdbServer.py)
FAIL: test_p_returns_correct_data_size_for_each_qRegisterInfo_launch_llgs (tools/lldb-server/TestLldbGdbServer.py)
FAIL: test_register_commands_dwarf (functionalities/register/register_command/TestRegisters.py)
FAIL: test_register_commands_dwo (functionalities/register/register_command/TestRegisters.py)
FAIL: test_register_commands_gmodules (functionalities/register/register_command/TestRegisters.py)
FAIL: test_register_expressions_dwarf (functionalities/register/register_command/TestRegisters.py)
FAIL: test_register_expressions_dwo (functionalities/register/register_command/TestRegisters.py)
FAIL: test_register_expressions_gmodules (functionalities/register/register_command/TestRegisters.py)
FAIL: test_setpgid_dwarf (expression_command/expr-in-syscall/TestExpressionInSyscall.py)
FAIL: test_setpgid_dwarf (functionalities/process_group/TestChangeProcessGroup.py)
FAIL: test_setpgid_dwo (expression_command/expr-in-syscall/TestExpressionInSyscall.py)
FAIL: test_setpgid_dwo (functionalities/process_group/TestChangeProcessGroup.py)
FAIL: test_setpgid_gmodules (functionalities/process_group/TestChangeProcessGroup.py)
FAIL: test_setpgid_gmodules (expression_command/expr-in-syscall/TestExpressionInSyscall.py)
FAIL: test_with_python_dwarf (functionalities/return-value/TestReturnValue.py)
FAIL: test_with_python_dwo (functionalities/return-value/TestReturnValue.py)
FAIL: test_with_python_gmodules (functionalities/return-value/TestReturnValue.py)

[shahmishal]

@swift-ci Please smoke test

[shahmishal]

@tfiala We should revert this soon as we get Linux test passing on Ubuntu 14.04 system. Thanks!