Expand Trigger parsing support

Hi folks,

Thanks @LucaCappelletti94 for stepping in. I was very excited to see "CREATE TRIGGER" support landing.

I just tried it it out and noticed that it's implemented for the Postgres and Generic dialects only, which is a great. I was wondering if there are any plans to extend support to other dialects? I'm most interest in sqlite: https://www.sqlite.org/lang_createtrigger.html with the biggest difference being inline functions bodies vs "execute function_name"

Thanks!

首先阅读现有的 Postgres 和 Generic 方言的 CREATE TRIGGER 解析支持，然后将其与链接的 SQLite 文档中的 SQLite CREATE TRIGGER 语法进行比较。完成的标准是：SQLite 触发器语句（包括内联函数体）能够被接受，并由适当的解析器测试覆盖。

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