Fix 空指针 (Null pointer) of case 17 paddle.flip

[RedContritio]

PR types

Bug fixes

PR changes

OPs

Describe

• 空指针 (Null pointer) #49922
• good first issue lists #49927

Solution

要求 flip 的 axis 必须为 int 或维度为 1（tuple|list|tensor)。

[paddle-bot]

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[paddle-bot]

很抱歉，经过我们的反复讨论，你的PR暂未达到合入标准，请阅读飞桨原生算子开发规范，你可以重新提交新的PR，我们先将此PR关闭，感谢你的贡献。
Sorry to inform you that through our discussion, your PR fails to meet the merging standard (Reference: Paddle Custom Operator Design Doc). You can also submit an new one. Thank you.

[paddle-bot]

很抱歉，经过我们的反复讨论，你的PR暂未达到合入标准，请阅读飞桨原生算子开发规范，你可以重新提交新的PR，我们先将此PR关闭，感谢你的贡献。
Sorry to inform you that through our discussion, your PR fails to meet the merging standard (Reference: Paddle Custom Operator Design Doc). You can also submit an new one. Thank you.