Improve `SnowflakeDecode`

[tamaroning]

The current implementation cannot decode some types.
For example, only true and false are expected for booleans but API may return true, t, yes, y, on, 1, etc.
https://docs.snowflake.com/en/sql-reference/data-types-logical#boolean-conversion

[tamaroning]

Supported Snowflake types and corresponding Rust types

• boolean: bool
• text: String
• fixed, real: f64
• time: chrono::NativeTime
• date: chrono::NativeDate
• timestamp_ntz/ltz/tz: chrono::NativeDateTime
  • ltz may not be supported for now. TODO: check
• array: Vec
• object: TBA
• variant: TBA
• map: HashMap<String, f64>
• GEOGRAPHY: TBA
• GEOMETRY: TBA