Fix the linting problems in UnsafeBufferUsage.cpp

Fix the linting problems which causes `clang/utils/ci/run-buildbot check-format` to return 1.

Also make a correction for the email address of the author of
0fd41759:

  The correct email address is "ar.ashouri999@gmail.com", not "ar.ashouri999@google.com".

Reviewed by: ziqingluo-90 (Ziqing Luo)

Differential revision: https://reviews.llvm.org/D155814