feat: add task source providers [WIP]

[acesyde]

[!NOTE] Here is a complete draft implementation of a new task source implementation

Motivation

• Share common tasks across repositories without rewriting them
• Pin task version to avoid potential drift.

Sample

[my_local_task]
file = "scripts/release.sh"

[my_https_task]
file = "https://example.com/modules/deploy"

[my_git_ssh_task]
file = "git::ssh://[email protected]:user/repo.git//path/to/task?ref=develop"

[my_git_https_task]
file = "git::https://github.com/user/repo.git//path/to/task?ref=develop"

[my_s3_task]
file = "s3::https://s3.amazonaws.com/my-bucket/modules/cleanup"

Questions

• The file property no longer corresponds to the usage, it would be better to put source for example ?
• Manage these tasks in a cache and avoid an excessive amount of download if the git source is already used (tuple url + ref)