Workaround broken constexpr in MSVC
Workaround broken constexpr in MSVC

Summary: `constexpr` is known to be broken in MSVC causing errors when using format string compilation so disable `FMT_COMPILE` there.

Reviewed By: neildhar

Differential Revision: D26019769

fbshipit-source-id: b823b24d4e73fcf9632f8e648ebb9a4e73c43bb1

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