Fix documentation deployment pipeline

[cwschilly]

We're getting an import error when we deploy documentation, based on the JSON validator loader:

Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.8.18/x64/bin/lbaf-vt-data-files-validator-loader", line 5, in <module>
    from lbaf import vt_data_files_validator_loader
  File "/home/runner/work/LB-analysis-framework/LB-analysis-framework/src/lbaf/__init__.py", line 18, in <module>
    from lbaf.Applications.LBAF_app import LBAFApplication
  File "/home/runner/work/LB-analysis-framework/LB-analysis-framework/src/lbaf/Applications/LBAF_app.py", line 21, in <module>
    from lbaf.Execution.lbsRuntime import Runtime
  File "/home/runner/work/LB-analysis-framework/LB-analysis-framework/src/lbaf/Execution/lbsRuntime.py", line 4, in <module>
    from ..Execution.lbsAlgorithmBase import AlgorithmBase
  File "/home/runner/work/LB-analysis-framework/LB-analysis-framework/src/lbaf/Execution/lbsAlgorithmBase.py", line 7, in <module>
    from ..Model.lbsPhase import Phase
  File "/home/runner/work/LB-analysis-framework/LB-analysis-framework/src/lbaf/Model/lbsPhase.py", line 7, in <module>
    from ..Execution.lbsPhaseSpecification import PhaseSpecification
  File "/home/runner/work/LB-analysis-framework/LB-analysis-framework/src/lbaf/Execution/lbsPhaseSpecification.py", line 8, in <module>
    from typing_extensions import NotRequired
ModuleNotFoundError: No module named 'typing_extensions'

(from this CI run)