script: remove out-of-date snprintf TODO

that was resolved in PR27036 "test: Remove last uses of snprintf and simplify"
and while here, fix up 2 words in docs to make the spelling linter green again.

test/lint/lint-locale-dependence.py

@@ -34,8 +34,6 @@
 #
 # See https://doc.qt.io/qt-5/qcoreapplication.html#locale-settings and
 # https://stackoverflow.com/a/34878283 for more details.
-#
-# TODO: Reduce KNOWN_VIOLATIONS by replacing uses of locale dependent snprintf with strprintf.
 
 import re
 import sys