maint: convert `...' to '...' in --help output

All affected lines end with \ or \n\, so run this command
until it produces no new changes (4 times):
  git grep -E -l '`[^ ]+'\''.*\\' src \
    |xargs perl -pi -e 's/`([^ ]+'\''.*\\)/'\''$1/'

1 files changed, 1 insertions, 1 deletions

diff --git a/src/yes.c b/src/yes.c
index 535c13fe0..1084f442f 100644
--- a/src/yes.c
+++ b/src/yes.c
@@ -45,7 +45,7 @@ Usage: %s [STRING]...\n\
               program_name, program_name);
 
       fputs (_("\
-Repeatedly output a line with all specified STRING(s), or `y'.\n\
+Repeatedly output a line with all specified STRING(s), or 'y'.\n\
 \n\
 "), stdout);
       fputs (HELP_OPTION_DESCRIPTION, stdout);