Merging r353700:

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r353700 | mgorny | 2019-02-11 06:09:43 -0800 (Mon, 11 Feb 2019) | 7 lines

[lldb] [test] Skip lldb-mi test if LLDB_DISABLE_PYTHON is used

Skip running lldb-mi tests when Python support is disabled.  This causes
lldb-mi to unconditionally fail, and therefore all the relevant tests
fail as well.

Differential Revision: https://reviews.llvm.org/D58000
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llvm-svn: 362016