patch 8.2.0573: using :version twice leaks memory

Problem:    using :version twice leaks memory
Solution:   Only initialize variables once. (Dominique Pelle, closes #5917)
diff --git a/src/testdir/Make_all.mak b/src/testdir/Make_all.mak
index 63d97e8..db74f05 100644
--- a/src/testdir/Make_all.mak
+++ b/src/testdir/Make_all.mak
@@ -285,6 +285,7 @@
 	test_utf8 \
 	test_utf8_comparisons \
 	test_vartabs \
+	test_version \
 	$(TEST_VIM9) \
 	test_viminfo \
 	test_vimscript \