patch 8.2.2755: Vim9: no error for using a number in a condition

Problem:    Vim9: no error for using a number in a condition.
Solution:   Also use ISN_COND2BOOL if the type is t_number_bool.
            (closes #7644)
diff --git a/src/vim9compile.c b/src/vim9compile.c
index 15d2c30e..59d1339 100644
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -990,7 +990,7 @@
     if (type == &t_bool)
 	return OK;
 
-    if (type == &t_any || type == &t_number)
+    if (type == &t_any || type == &t_number || type == &t_number_bool)
 	// Number 0 and 1 are OK to use as a bool.  "any" could also be a bool.
 	// This requires a runtime type check.
 	return generate_COND2BOOL(cctx);