New feature: Allow Configurator::into_builder() to convert into a corresponding builder

[Xuanwo]

Feature Description

opendal/core/src/types/builder.rs

Lines 97 to 111 in e05e310

	pub trait Configurator: Serialize + DeserializeOwned + Debug + 'static {
	/// Deserialize from an iterator.
	///
	/// This API is provided by opendal, developer should not implement it.
	fn from_iter(iter: impl IntoIterator<Item = (String, String)>) -> Result<Self> {
	let cfg = ConfigDeserializer::new(iter.into_iter().collect());
	Self::deserialize(cfg).map_err(|err| {
	Error::new(ErrorKind::ConfigInvalid, "failed to deserialize config").set_source(err)
	})
	}
	/// Convert this configuration into a service builder.
	fn into_builder(self) -> impl Builder;
	}

Configurator::into_builder now returns impl Builder, resulting in the absence of its type information. This prohibits us from parsing the config into S3Config and then converting S3Config into S3Builder. Consequently, users are unable to add more settings for the HTTP client.

Problem and Solution

Let's introduce Builder as an associated type within Configurator.

Additional Context

No response

Are you willing to contribute to the development of this feature?

• Yes, I am willing to contribute to the development of this feature.