chore(deps): update dependency sphinx-rtd-theme to v3

This MR contains the following updates:

Package	Type	Update	Change
sphinx-rtd-theme	dev-dependencies	major	^1.0.0 -> ^1.0.0 || ^3.0.0

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Release Notes

readthedocs/sphinx_rtd_theme (sphinx-rtd-theme)

v3.0.2

Compare Source

v3.0.1

Compare Source

v3.0.0

Compare Source

v2.0.0

Compare Source

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