[clang-format] Don't put `noexcept` on empty line following constructor

With the AlwaysBreakTemplateDeclarations option, having a constructor
template for a type consisting of all-uppercase letters with a
noexcept specifier would put said noexcept specifier on its own blank
line.

This is because the all-uppercase type is understood as a macro-like
attribute (such as DEPRECATED()), and noexcept is seen as the
declaration. However, noexcept is a keyword and cannot be an
identifier on its own.

Fixes https://github.com/llvm/llvm-project/issues/56216

Differential Revision: https://reviews.llvm.org/D132189