[clang-tidy] Made abseil-faster-strsplit-delimiter tests pass on C++17

Reviewers: hokein, gribozavr

Reviewed By: hokein, gribozavr

Subscribers: xazax.hun, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D63253

Patch by Johan Vikström.

llvm-svn: 363273