[clang-format] Fix Microsoft style for enums

Summary:
Before this change enums were formatted incorrectly for the Microsoft style.

[C++ Example]

    enum {
      one,
      two
    } three, four;

[Incorrectly Formatted]

    enum
    {
      one,
      two
    } three,
        four;

[Correct Format with Patch]

    enum
    {
      one,
      two
    } three, four;

Reviewers: jbcoe, MyDeveloperDay, rnk

Reviewed By: MyDeveloperDay

Subscribers: cfe-commits

Tags: #clang, #clang-format

Differential Revision: https://reviews.llvm.org/D78982