Update pydata-sphinx-theme requirement from >=0.19.0 to >=0.20.0 in /docs/source - #146

Warning: Code scanning cannot determine the alerts introduced by this pull request, because 3 configurations present on refs/heads/main were not found:

Default setup

• ❓  /language:actions
• ❓  /language:c-cpp
• ❓  /language:python

View all branch alerts.