Add workflow for multi-version sphinx docs

[niksirbi]

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Description

What is this PR

• [ ] Bug fix
• [ ] Addition of a new feature
• [ ] Other

Why is this PR needed?

What does this PR do?

References

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How has this PR been tested?

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Is this a breaking change?

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Does this PR require an update to the documentation?

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Checklist:

• [ ] The code has been tested locally
• [ ] Tests have been added to cover all new functionality
• [ ] The documentation has been updated to reflect any changes
• [ ] The code has been formatted with pre-commit