[Feature Request]: Specify pipx version

[xiaoyao9184]

Requested Feature

Given the application scenario of devcontainers, it should be possible to create identical environments from the same json file, so specifying the version of pipx should bring this goal one step closer, which will avoid upstream software compatibility modifications that would break devcontainers, like this pypa/pipx#1444

[evilhamsterman]

This project is not associated with the devcontainer project and appears to have been abandoned #628 . The official project has removed all devcontainer-contrib features from their listing. devcontainers/devcontainers.github.io#451. There is a fork that is being worked on to update and maintain the features https://github.com/devcontainers-extra/features