patch 8.2.1261: Vim9: common type of function not tested

Problem:    Vim9: common type of function not tested.
Solution:   Add a test.  Fix uncovered problems.
diff --git a/src/vim9execute.c b/src/vim9execute.c
index f022b5b..d83ac5a 100644
--- a/src/vim9execute.c
+++ b/src/vim9execute.c
@@ -2470,6 +2470,7 @@
 	if (func_return(&ectx) == FAIL)
 	    // only fails when out of memory
 	    goto failed;
+	continue;
 
 on_error:
 	if (trylevel == 0)