* Add default_expr support for ColumnDef
* added test for attribute `default_value`
* Implements `PartialEq` for `sea_query::SimpleExpr`
* RcOrArc
* Re-export `sea_query::Expr` in `sea_orm::entity::prelude`
* Add default_expr support for ColumnDef
* added test for attribute `default_value`
* Implements `PartialEq` for `sea_query::SimpleExpr`
* RcOrArc
* Re-export `sea_query::Expr` in `sea_orm::entity::prelude`
* Deprecate `ColumnDef::default_value()`
* Add `ColumnDef::default()`
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Co-authored-by: Billy Chan <ccw.billy.123@gmail.com>