patch 8.0.0658: spell test is old style

Problem:    Spell test is old style.
Solution:   Turn the spell test into a new style test (pschuh, closes #1778)
diff --git a/src/Makefile b/src/Makefile
index 500b074..10049df 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -2086,7 +2086,7 @@
 	test20 test21 test22 test23 test24 test25 test26 test27 test28 test29 \
 	test30 test31 test32 test33 test34 test36 test37 test38 test39 \
 	test40 test41 test42 test43 test44 test45 test48 test49 \
-	test50 test51 test52 test53 test54 test55 test56 test57 test58 test59 \
+	test50 test51 test52 test53 test54 test55 test56 test57 test59 \
 	test60 test64 test66 test67 test68 test69 \
 	test70 test72 test73 test74 test75 test77 test78 test79 \
 	test80 test82 test83 test84 test85 test86 test87 test88 \