Remove README (copy/paste error) from MPIConfig module
Summary
Remove README from the module which is not related to mpi (template remote module) and remove unused cmake option from the CMakeLists
Rationale
Explain the rationale for the changes (possible link to a Request For Comments or to an issue).
Implementation Details
Classes and files
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Applications
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Tests
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Documentation
List or link documentation modifications that were made (doxygen, example, software guide, application documentation, cookbook).
Additional notes
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