tests: change `...' to '...' on lines not matching /[=\$]/

Exempt lines with '$' or '=', since those are prone to improper
conversion.  Run this:
  git grep -l "\`[^']*'" tests \
   |xargs perl -pi -e '/[=\$]/ and next;s/\`([^'\''"]*?'\'')/'\''$1/g'

1 files changed, 1 insertions, 1 deletions

diff --git a/tests/rm/empty-name b/tests/rm/empty-name
index 58fb8505d..192a60b4b 100755
--- a/tests/rm/empty-name
+++ b/tests/rm/empty-name
@@ -18,7 +18,7 @@
 
 # On SunOS 4.1.3, running rm -r '' in a nonempty directory may
 # actually remove files with names of entries in the current directory
-# but relative to `/' rather than relative to the current directory.
+# but relative to '/' rather than relative to the current directory.
 
 use strict;