Remove DES Y1 and SRD SN examples

[marcpaterno]

Description

Remove the examples/des_y1_3x2pt and examples/srd_sn directories and their contents, including Python
scripts, configuration files, notebooks, and data
files.

Update test files and tutorials to reference
tests/sacc_data.hdf5 instead of the removed
examples/des_y1_3x2pt/sacc_data.hdf5.

Remove slow tests that relied on the DES Y1
example data and configuration files from:

• test_model_likelihood.py
• test_numcosmo_connector.py
• test_factories.py

Update tutorial Quarto documents to use the test
data path.

Type of change

Please delete the bullet items below that do not apply to this pull request.

• Refactoring: remove needless examples

Checklist:

The following checklist will make sure that you are following the code style and
guidelines of the project as described in the
contributing page.

• I have run bash pre-commit-check and fixed any issues
• I have added tests that prove my fix is effective or that my feature works
• I have made corresponding changes to the documentation
• I have 100% test coverage for my changes (please check this after the CI system has verified the coverage)