ci: Use lockfiles to control cached venv

[thomass-dev]

Closes #1146 .

This PR intends to fix all the dependencies used in the CI in multiple test-requirements.txt files, in a fully automated way.
It ensures that between two runs, the CI can't break because of a dependency update.
It bases the pipelines cache on these files.

On the other hand, it makes it easier to update the versions of the dependencies used in the CI.
Currently, the versions are updated only if someone updates the pyproject.toml file, or if the CI cache is purged by hand.
It will be now automatically updated each week by dependabot, in a pull-request.

This PR updates the dependabot configuration, but I can't be sure it works before the merge. If not, we can easily create a cron pipeline calling the new pip-compile.sh script.

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This PR adds a new backend test ensuring that test-requirements.txt files are regenerated when requirements.in or test-requirements.in is modified.

[github-actions]

Coverage Report for backend

File	Stmts	Miss	Cover	Missing
venv/lib/python3.12/site-packages/skore
__init__.py	14	0	100%
__main__.py	8	8	0%	3–19
exceptions.py	4	4	0%	4–23
venv/lib/python3.12/site-packages/skore/cli
__init__.py	5	5	0%	3–8
cli.py	22	22	0%	3–70
color_format.py	49	49	0%	3–116
venv/lib/python3.12/site-packages/skore/persistence
__init__.py	0	0	100%
venv/lib/python3.12/site-packages/skore/persistence/item
__init__.py	56	3	93%	96–99
altair_chart_item.py	24	1	93%	15
item.py	24	1	96%	86
matplotlib_figure_item.py	42	1	96%	19
media_item.py	24	0	100%
numpy_array_item.py	29	1	94%	16
pandas_dataframe_item.py	31	1	94%	14
pandas_series_item.py	31	1	94%	14
pickle_item.py	33	0	100%
pillow_image_item.py	32	1	94%	16
plotly_figure_item.py	25	1	93%	15
polars_dataframe_item.py	29	1	94%	14
polars_series_item.py	24	1	93%	14
primitive_item.py	25	2	91%	13–15
sklearn_base_estimator_item.py	31	1	94%	15
skrub_table_report_item.py	10	1	86%	11
venv/lib/python3.12/site-packages/skore/persistence/repository
__init__.py	3	0	100%
item_repository.py	59	5	91%	15–16, 202–203, 226
view_repository.py	19	2	86%	9–10
venv/lib/python3.12/site-packages/skore/persistence/storage
__init__.py	4	0	100%
abstract_storage.py	22	0	100%
disk_cache_storage.py	33	1	95%	44
in_memory_storage.py	20	0	100%
venv/lib/python3.12/site-packages/skore/persistence/view
__init__.py	2	0	100%
view.py	5	0	100%
venv/lib/python3.12/site-packages/skore/project
__init__.py	3	0	100%
_launch.py	150	1	99%	278
_open.py	9	0	100%
project.py	71	1	99%	250
venv/lib/python3.12/site-packages/skore/sklearn
__init__.py	4	0	100%
_base.py	140	4	97%	91, 94, 168–>173, 183–184
find_ml_task.py	45	3	91%	71–>87, 84–86
types.py	2	0	100%
venv/lib/python3.12/site-packages/skore/sklearn/_cross_validation
__init__.py	6	0	100%
metrics_accessor.py	163	0	100%
report.py	87	0	100%
venv/lib/python3.12/site-packages/skore/sklearn/_estimator
__init__.py	6	0	100%
metrics_accessor.py	265	4	97%	149–158, 183–>236, 191, 434–>437, 783–>786
report.py	120	0	99%	213–>219, 221–>223
utils.py	11	11	0%	1–19
venv/lib/python3.12/site-packages/skore/sklearn/_plot
__init__.py	4	0	100%
precision_recall_curve.py	121	1	98%	229–>246, 317
prediction_error.py	97	0	100%
roc_curve.py	128	0	100%
utils.py	88	0	100%
venv/lib/python3.12/site-packages/skore/sklearn/train_test_split
__init__.py	0	0	100%
train_test_split.py	36	2	94%	16–17
venv/lib/python3.12/site-packages/skore/sklearn/train_test_split/warning
__init__.py	8	0	100%
high_class_imbalance_too_few_examples_warning.py	17	3	78%	16–18, 80
high_class_imbalance_warning.py	18	2	88%	16–18
random_state_unset_warning.py	11	1	87%	15
shuffle_true_warning.py	9	0	91%	44–>exit
stratify_is_set_warning.py	11	1	87%	15
time_based_column_warning.py	22	1	89%	17, 69–>exit
train_test_split_warning.py	5	1	80%	21
venv/lib/python3.12/site-packages/skore/ui
__init__.py	0	0	100%
app.py	32	32	0%	3–83
dependencies.py	4	4	0%	3–10
project_routes.py	62	62	0%	3–145
server.py	17	17	0%	3–40
venv/lib/python3.12/site-packages/skore/utils
__init__.py	6	0	100%
_accessor.py	7	0	100%
_environment.py	26	0	97%	29–>34
_logger.py	21	4	84%	14–18
_patch.py	11	5	46%	19–35
_progress_bar.py	30	0	100%
_show_versions.py	31	0	100%
TOTAL	2643	273	90%

Tests	Skipped	Failures	Errors	Time
547	3 💤	0 ❌	0 🔥	53.764s ⏱️

[github-actions]

Documentation preview @ aac6dab

[rouk1]

To be honest I do not fully understand what is going on here. This definitely needs an ADR, hence enlarging the scope of #1066.

[thomass-dev]

To be honest I do not fully understand what is going on here. This definitely needs an ADR, hence enlarging the scope of #1066.

I have written two ADRs. Hope it helps you to understand the context of this PR.

[rouk1]

Sounds good to me thanks @thomass-dev for the documentation.
LGTM !

We may need another ADR to globally explain all the CI actions and workflows but this should be done in another PR obviously.