patch 8.0.0890: still many old style tests

Problem:    Still many old style tests.
Solution:   Convert several tests to new style. (Yegappan Lakshmanan)
diff --git a/src/testdir/Make_all.mak b/src/testdir/Make_all.mak
index f8ce3fa..678fc80 100644
--- a/src/testdir/Make_all.mak
+++ b/src/testdir/Make_all.mak
@@ -38,7 +38,6 @@
 	test44.out \
 	test45.out \
 	test48.out \
-	test51.out \
 	test53.out \
 	test55.out \
 	test56.out \
@@ -53,12 +52,9 @@
 	test79.out \
 	test80.out \
 	test88.out \
-	test91.out \
 	test94.out \
 	test95.out \
 	test99.out \
-	test103.out \
-	test107.out \
 	test108.out \
 	test_autoformat_join.out \
 	test_changelist.out \
@@ -140,6 +136,7 @@
 	    test_file_size.res \
 	    test_fnameescape.res \
 	    test_fold.res \
+	    test_getvar.res \
 	    test_gf.res \
 	    test_gn.res \
 	    test_gui.res \
@@ -147,6 +144,7 @@
 	    test_hardcopy.res \
 	    test_help.res \
 	    test_hide.res \
+	    test_highlight.res \
 	    test_history.res \
 	    test_hlsearch.res \
 	    test_increment.res \