patch 8.0.0443: terminal width is set to 80 in test3

Problem:    Terminal width is set to 80 in test3.
Solution:   Instead of setting 'columns' set 'wrapmargin' depending on
            'columns.
diff --git a/src/testdir/test3.in b/src/testdir/test3.in
index 9e66436..c78a66e 100644
--- a/src/testdir/test3.in
+++ b/src/testdir/test3.in
Binary files differ