patch 9.1.0335: String interpolation fails for List type

Problem:  String interpolation fails for List type
Solution: use implicit string(list) for string interpolation and :put =
          (Yegappan Lakshmanan)

related: #14529
closes: #14556

Signed-off-by: Yegappan Lakshmanan <yegappan@yahoo.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/vim9compile.c b/src/vim9compile.c
index 7e1d911..0e05f82 100644
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -1222,7 +1222,7 @@
     }
     if (compile_expr0(&block_start, cctx) == FAIL)
 	return NULL;
-    may_generate_2STRING(-1, TRUE, cctx);
+    may_generate_2STRING(-1, TOSTRING_INTERPOLATE, cctx);
 
     return block_end + 1;
 }
@@ -2421,7 +2421,7 @@
 	    return FAIL;
 	}
 	if (dest_type == VAR_DICT
-			      && may_generate_2STRING(-1, FALSE, cctx) == FAIL)
+		&& may_generate_2STRING(-1, TOSTRING_NONE, cctx) == FAIL)
 	    return FAIL;
 	if (dest_type == VAR_LIST || dest_type == VAR_BLOB)
 	{
@@ -2975,7 +2975,7 @@
 
 	    if (*op == '.')
 	    {
-		if (may_generate_2STRING(-1, FALSE, cctx) == FAIL)
+		if (may_generate_2STRING(-1, TOSTRING_NONE, cctx) == FAIL)
 		    goto theend;
 	    }
 	    else