Extension causes issue when {exercise} and {solution} aren't used but extension is loaded #46
Description
Describe the problem
Extension causes issue when {exercise} and {solution} aren't used but extension is loaded
Link to your repository or website
QuantEcon/lecture-datascience.myst#199
Steps to reproduce
Build the lecture-datascience.myst quantecon lecture site
The version of Python you're using
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Your operating system
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Versions of your packages
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Additional context
To resolve this I need to ensure the sphinx_exercise_registry is initialised when the extension is loaded.