[clang-format] Add option for aligning requires clause body

Adds an option whether requires clause body should be aligned with
the `requires` keyword.
This option is now the default, both without configuration and in LLVM
style.

Fixes https://github.com/llvm/llvm-project/issues/56283

Differential Revision: https://reviews.llvm.org/D129443



Co-authored-by: Emilia Dreamer <emilia@rymiel.space>