[clang-format] Don't allow template to be preceded by closing brace

This check is similar to the right paren check right below it, but it
doesn't need the overloaded operator check.

This patch prevents brace-initialized objects that are being compared
from being mis-annotated as template parameters.

Fixes https://github.com/llvm/llvm-project/issues/57004

Reviewed By: owenpan, MyDeveloperDay

Differential Revision: https://reviews.llvm.org/D150629