Add Support for upsert Semantics in save Method for PostgreSQL

[FWangZil]

1. What version of Go and system type/arch are you using?

go version go1.20.9 darwin/arm64

2. What version of GoFrame are you using?

v2.5.4

3. Can this issue be re-produced with the latest release?

Yes.

4. What did you do?

I attempted to use the save method with PostgreSQL as the database.

5. What did you expect to see?

I expected the save method to support PostgreSQL, especially since PostgreSQL already supports the upsert operation. I suggest adding support for the upsert semantics. For reference, here's the official PostgreSQL documentation.

6. What did you see instead?

I received a message indicating that PostgreSQL is not supported by the save method.

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[github-actions]

Hello @FWangZil. We like your proposal/feedback and would appreciate a contribution via a Pull Request by you or another community member. We thank you in advance for your contribution and are looking forward to reviewing it!
你好 @FWangZil。我们喜欢您的提案/反馈，并希望您或其他社区成员通过拉取请求做出贡献。我们提前感谢您的贡献，并期待对其进行审查。