implement http-body 1.0 for PathBody (#3673)

## Motivation and Context
<!--- Why is this change required? What problem does it solve? -->
<!--- If it fixes an open issue, please link to the issue here -->
#1925 

## Description
<!--- Describe your changes in detail -->
Implements the v1 `http_body::Body` trait for `PathBody`. Part of the
ongoing hyper v1 upgrade.
This also moves a pre-1.0 impl into its own module.

## Testing
<!--- Please describe in detail how you tested your changes -->
<!--- Include details of your testing environment, and the tests you ran
to -->
<!--- see how your change affects other areas of the code, etc. -->
I ported the tests too

## Checklist
<!--- If a checkbox below is not applicable, then please DELETE it
rather than leaving it unchecked -->
- [x] I have updated `CHANGELOG.next.toml` if I made changes to the
smithy-rs codegen or runtime crates
- [x] I have updated `CHANGELOG.next.toml` if I made changes to the AWS
SDK, generated SDK code, or SDK runtime crates

----

_By submitting this pull request, I confirm that you can use, modify,
copy, and redistribute this contribution, under the terms of your
choice._

Author: Zelda Hessler

CHANGELOG.next.toml

@@ -11,6 +11,18 @@
 # meta = { "breaking" = false, "tada" = false, "bug" = false, "target" = "client | server | all"}
 # author = "rcoh"
 
+ [[aws-sdk-rust]]
+ message = "Add support for v1 `http_body::Body` to `aws_smithy_types::byte_stream::bytestream_util::PathBody`."
+ references = ["smithy-rs#1925", "smithy-rs#3673"]
+ meta = { "breaking" = false, "tada" = false, "bug" = false }
+ author = "Velfi"
+
+ [[smithy-rs]]
+ message = "Add support for v1 `http_body::Body` to `aws_smithy_types::byte_stream::bytestream_util::PathBody`."
+ references = ["smithy-rs#1925", "smithy-rs#3673"]
+ meta = { "breaking" = false, "tada" = false, "bug" = false, "target" = "all"}
+ author = "Velfi"
+
 [[smithy-rs]]
 message = "Reduce verbosity of various debug logs"
 references = ["smithy-rs#3664"]

rust-runtime/aws-smithy-types/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "aws-smithy-types"
-version = "1.1.10"
+version = "1.2.0"
 authors = [
     "AWS Rust SDK Team <[email protected]>",
     "Russell Cohen <[email protected]>",

rust-runtime/aws-smithy-types/src/byte_stream.rs

@@ -149,6 +149,7 @@ pub use self::bytestream_util::FsBuilder;
 /// The name has a suffix `_x` to avoid name collision with a third-party `http-body-0-4`.
 #[cfg(feature = "http-body-0-4-x")]
 pub mod http_body_0_4_x;
+
 #[cfg(feature = "http-body-1-x")]
 pub mod http_body_1_x;