This patch replaces uses of StringRef::{starts,ends}with with
StringRef::{starts,ends}_with for consistency with
std::{string,string_view}::{starts,ends}_with in C++20.
I'm planning to deprecate and eventually remove
StringRef::{starts,ends}with.
It fittingly already makes use of add_llvm_utility during target creation and is usually only used in conjunction with other (test) related utilities such as FileCheck and not, which are already in utils.
Differential Revision: https://reviews.llvm.org/D131713