Fix test command in documentation

[Bobo1239]

Description/Motivation/Screenshots

Just a fix for the documentation for anybody not familiar with pytest (like me).

Against which architecture was this tested ?

"Tested" indicates that the PR works and the unit test (see docs/testing.md) run passes without issue.

• x86-32
• x86-64
• ARM
• AARCH64
• MIPS
• POWERPC
• SPARC
• RISC-V

Checklist

• My PR was done against the dev branch, not main.
• My code follows the code style of this project.
• My change includes a change to the documentation, if required.
• If my change adds new code, adequate tests have been added.
• I have read and agree to the CONTRIBUTING document.

[Grazfather]

I don't think we need the tests part.

[Bobo1239]

Hm, at least with my setup (Arch Linux) I get:
without tests:

bobo1239@WORKSTATION-ARCH ~/D/R/gef> python3 -m pytest -v -k "not benchmark"
===================================================== test session starts ======================================================
platform linux -- Python 3.10.8, pytest-7.1.3, pluggy-1.0.0 -- /usr/bin/python3
cachedir: .pytest_cache
benchmark: 3.4.1 (defaults: timer=time.perf_counter disable_gc=False min_rounds=5 min_time=0.000005 max_time=1.0 calibration_precision=10 warmup=False warmup_iterations=100000)
rootdir: /home/bobo1239/Development/Random/gef
plugins: cov-4.0.0, xdist-3.0.0, benchmark-3.4.1, forked-1.4.0
collected 0 items

==================================================== no tests ran in 0.02s =====================================================

with tests:

bobo1239@WORKSTATION-ARCH ~/D/R/gef> python3 -m pytest -v -k "not benchmark" tests
===================================================== test session starts ======================================================
platform linux -- Python 3.10.8, pytest-7.1.3, pluggy-1.0.0 -- /usr/bin/python3
cachedir: .pytest_cache
benchmark: 3.4.1 (defaults: timer=time.perf_counter disable_gc=False min_rounds=5 min_time=0.000005 max_time=1.0 calibration_precision=10 warmup=False warmup_iterations=100000)
rootdir: /home/bobo1239/Development/Random/gef/tests, configfile: pytest.ini
plugins: cov-4.0.0, xdist-3.0.0, benchmark-3.4.1, forked-1.4.0
collected 118 items / 3 deselected / 115 selected

tests/api/deprecated.py::GefFuncDeprecatedApi::test_deprecated_elf_values
...

[Grazfather]

Thank you