fix(s2n-quic-core): optimize Bytes read on full read

[camshaft]

Description of changes:

This change optimizes a read to a Bytes/BytesMut when the watermark consumes the entire chunk. In this case, it doesn't matter if the caller optimizes on bytes or not - it's better to replace self with an empty instance and return the chunk to potentially avoid copies.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[Copilot]

Copilot reviewed 1 out of 1 changed files in this pull request and generated no comments.

Comments suppressed due to low confidence (2)

quic/s2n-quic-core/src/buffer/reader/storage/bytes.rs:50

• [nitpick] The variable name 'consumes_self' may be unclear; consider renaming it to 'is_full_read' to clearly indicate that it checks whether the entire buffer is being read.

let consumes_self = watermark == self.len();

quic/s2n-quic-core/src/buffer/reader/storage/bytes.rs:102

• [nitpick] The variable name 'consumes_self' may be unclear in this context as well; consider renaming it to 'is_full_read' for consistency and improved readability.

let consumes_self = watermark == self.len();