[cleanup][strings] Remove redundant NOLINT annotations

cpplint rules change over time, and we change the exact rules we enable
for v8. This CL removes NOLINT annotations which are not needed
according to the currently enabled rules.

R=leszeks@chromium.org

Bug: v8:11717
Change-Id: I7b54d7c75ef474749e22599a4bf16d9d309f4436
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2859950
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74360}