patch 8.2.3893: Vim9: many local variables are initialized with an instruction

Problem:    Vim9: many local variables are initialized with an instruction.
Solution:   Initialize local variables to zero to avoid the instructions.
diff --git a/src/vim9cmds.c b/src/vim9cmds.c
index 5c7a938..4e5336c 100644
--- a/src/vim9cmds.c
+++ b/src/vim9cmds.c
@@ -2092,7 +2092,7 @@
 						      &t_string, cctx) == FAIL)
 		    return NULL;
 	    }
-	    else if (generate_store_lhs(cctx, lhs, -1) == FAIL)
+	    else if (generate_store_lhs(cctx, lhs, -1, FALSE) == FAIL)
 		return NULL;
 
 	    VIM_CLEAR(lhs->lhs_name);