URL is unable to be decoded

[jaekong]

Describe the bug

At some point after 2.3.0, PostgresKit cannot decode Foundation's URL struct stored in database.

To Reproduce

• I am using Vapor and Fluent. But I am guessing that it is reproducible on postgres-kit's own.

1. Use Vapor/Fluent and PostgresKit package 2.3.3.
2. Make a model with a URL field, and two endpoints - one for creating object, the other for fetching.
3. Send a request to create and store the object on the database.
4. Send another request to read the object.
5. See error below.

{
    "error": true,
    "reason": "invalid field: fieldname type: Optional error: typeMismatch(Swift.String, Swift.DecodingError.Context(codingPath: [], debugDescription: \"Expected to decode String but found a dictionary instead.\", underlyingError: nil))"
}

Expected behavior

An object with stored URL will be returned.

Environment

• Vapor Framework version: 4.52.1
• Vapor Toolbox version: 18.3.3
• OS version: macOS 12.0.1

Additional context

• Once I manually added PostgresKit 2.3.0 as dependency to my project, it started working just fine.
• Data is safely stored on the database, even on 2.3.3. The error only occurs when you try to decode it afterwards.