tests: Support /include/g++-v14/ libstdc++ header location (#504)

- Debian: /usr/x86_64-linux-gnu/include/c++/14/bits/basic_string.h
- Gentoo: /usr/lib/gcc/x86_64-pc-linux-gnu/14/include/g++-v14/bits/basic_string.h

Author: hartwork

tests/lcov/extract/extract.sh

@@ -226,7 +226,7 @@ if [ 0 != $? ] ; then
 fi
 
 # exclude some un-covered standard includes
-EXCLUDE='--exclude */include/c++/* --ignore unused'
+EXCLUDE='--exclude */include/c++/* --exclude */include/g++-v* --ignore unused'
 
 # callback tests
 echo $COVER $CAPTURE . $LCOV_OPTS -o callback.info $FILTER $IGNORE --criteria $SCRIPT_DIR/threshold.pm,--line,90,--branch,65,--function,100 $EXCLUDE