Pex

This release fixes resolving requirements from a lock using arbitrary
equality (`===`).

In addition, you can now "inject" runtime environment variables and
arguments into PEX files such that, when run, the PEX runtime ensures
those environment variables and command line arguments are passed to the
PEXed application. See [PEX Recipes](
https://docs.pex-tool.org/recipes.html#uvicorn-and-other-customizable-application-servers
)
for more information.

* Fix lock resolution to handle arbitrary equality. (1951)
* Support injecting args and env vars in a PEX. (1948)

This release fixes Pex runtime `sys.path` scrubbing for cases where Pex
is not the main entry point. An important example of this is in Lambdex
where the AWS Lambda Python runtime packages (`boto3` and `botocore`)
are leaked into the PEX runtime `sys.path`.

* Fix `sys.path` scrubbing. (1946)

This release brings musllinux wheel support and a fix for a regression
introduced in Pex 2.1.105 by 1902 that caused `PEX_PATH=` (an exported
`PEX_PATH` with an empty string value) to raise an error in almost all
use cases.

* Vendor latest packaging; support musllinux wheels. (1937)
* Don't treat `PEX_PATH=` as `.` like other PATHS. (1938)

This release fixes a latent PEX boot performance bug triggered by
requirements with large extras sets.

* Fix slow PEX boot time when there are many extras. (1929)

This release fixes an issue handling credentials in git+ssh VCS urls
when creating locks.

* Fix locks for git+ssh with credentials. (1923)

This release fixes a long-standing bug in handling direct reference
requirements with a local version component.

* Unquote path component of parsed url requirements (1920)