synopsis: Shallow and concurrent cloning of git repos
packages: cabal-install
prs: #10254

description: {

- Clone git repositories specified in source-repository-package stanzas
  shallowly, since to build the package from the repository we only need to
  read the commit specified. The rest of the repo is not needed.
  Note that this does not change the behaviour of `cabal get -s`, which will
  still clone the repository in full.
- Clone VCS repositories concurrently, with a maximum of two concurrent tasks
  at the same time (just like when downloading packages asynchronously)

}

