Add alt text (#64)

* Add alt text

* use python 3.10 on docs CI

---------

Co-authored-by: Jim Garrison <jim@garrison.cc>
Co-authored-by: Max Rossmannek <oss@zurich.ibm.com>

qiskit_addon_utils/problem_generators/generate_time_evolution_circuit.py

@@ -29,6 +29,7 @@ def generate_time_evolution_circuit(
     """Model the time evolution of an operator.
 
     .. plot::
+        :alt: Output from the previous code.
         :include-source:
 
         >>> from qiskit.quantum_info import SparsePauliOp

tox.ini

@@ -22,7 +22,7 @@ commands =
 
 [testenv:lint]
 image-tester-commit = 7ae965ccf21c39e5170334ec7f4882756883860a
-deps = 
+deps =
   git+https://github.com/Qiskit/documentation.git@{[testenv:lint]image-tester-commit}\#egg=sphinx-alt-text-validator&subdirectory=scripts/image-tester
 basepython = python3.10
 extras =
@@ -34,7 +34,7 @@ commands =
   nbqa ruff docs/
   mypy qiskit_addon_utils/
   pylint -rn qiskit_addon_utils/ test/
-  sphinx-alt-text-validator -f qiskit_addon_utils -s qiskit_addon_utils/problem_generators/generate_time_evolution_circuit.py
+  sphinx-alt-text-validator -f qiskit_addon_utils
   nbqa pylint -rn docs/
   typos
   reno lint