* Check git version before attempting to disable `sparse-checkout`
* Bump `MinimumGitSparseCheckoutVersion` to 2.28 due to #1386
* Initial prep for release 4.1.3

When a worktree is reused by actions/checkout and the first time sparse checkout was enabled, we need to ensure that the second time it is only a sparse checkout if explicitly asked for. Otherwise, we need to disable the sparse checkout so that a full checkout is the outcome of this Action.

## Details
* If no `sparse-checkout` parameter is specified, disable it

This should allow users to reuse existing folders when running
`actions/checkout` where a previous run asked for a sparse checkout but
the current run does not ask for a sparse checkout.

This fixes https://github.com/actions/checkout/issues/1475

There are use cases in particular with non-ephemeral (self-hosted) runners where an
existing worktree (that has been initialized as a sparse checkout) is
reused in subsequent CI runs (where `actions/checkout` is run _without_
any `sparse-checkout` parameter).

In these scenarios, we need to make sure that the sparse checkout is
disabled before checking out the files.

### Also includes:

* npm run build
* ci: verify that an existing sparse checkout can be made unsparse
* Added a clarifying comment about test branches.
* `test-proxy` now uses newly-minted `test-ubuntu-git` container image from ghcr.io

---------

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Co-authored-by: John Wesley Walker III <81404201+jww3@users.noreply.github.com>

* added filter option & tests

* added build file

* fix test oversight

* added exit 1

* updated docs to specify override

* undo unneeded readme change

* set to undefined rather than empty string

* run git config in correct di

---------

Co-authored-by: Cory Miller <13227161+cory-miller@users.noreply.github.com>

Setting the `show-progress` option to false in the `with` section of the
workflow step will cause git fetch to run without `--progress`.

The motivation is to be able to suppress the noisy progress status
output which adds many hundreds of "remote: Counting objects: 85%
(386/453)" and similar lines in the workflow log.

This should be sufficient to resolve #894 and its older friends,
though the solution is different to the one proposed there because
it doesn't use the --quiet flag. IIUC git doesn't show the progress
status by default since the output is not a terminal, so that's why
removing the --progress option is all that's needed.

Adding the --quiet flag doesn't make a lot of difference once the
--progress flag is removed, and actually I think using --quiet would
suppress some other more useful output that would be better left
visible.

Signed-off-by: Simon Baird <sbaird@redhat.com>

* Add option to fetch tags even if fetch-depth > 0

* Add jest tests for fetchDepth and fetchTags options

* Add support for sparse checkouts

* sparse-checkout: optionally turn off cone mode

While it _is_ true that cone mode is the default nowadays (mainly for
performance reasons: code mode is much faster than non-cone mode), there
_are_ legitimate use cases where non-cone mode is really useful.

Let's add a flag to optionally disable cone mode.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

* Verify minimum Git version for sparse checkout

The `git sparse-checkout` command is available only since Git version
v2.25.0. The `actions/checkout` Action actually supports older Git
versions than that; As of time of writing, the minimum version is
v2.18.0.

Instead of raising this minimum version even for users who do not
require a sparse checkout, only check for this minimum version
specifically when a sparse checkout was asked for.

Suggested-by: Tingluo Huang <tingluohuang@github.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

* Support sparse checkout/LFS better

Instead of fetching all the LFS objects present in the current revision
in a sparse checkout, whether they are needed inside the sparse cone or
not, let's instead only pull the ones that are actually needed.

To do that, let's avoid running that preemptive `git lfs fetch` call in
case of a sparse checkout.

An alternative that was considered during the development of this patch
(and ultimately rejected) was to use `git lfs pull --include <path>...`,
but it turned out to be too inflexible because it requires exact paths,
not the patterns that are available via the sparse checkout definition,
and that risks running into command-line length limitations.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

---------

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Co-authored-by: Daniel <daniel.fernandez@feverup.com>

* Adding the ability to specify the GitHub Server URL and allowing for it to differ from the Actions workflow host

* Adding tests for injecting the GitHub URL

* Addressing code review comments for PR #922

* Add set-safe-directory input to allow customers to take control.

* set safe directory when running checkout

* Update CHANGELOG.md

* Remove unneeded commit information from stdout