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

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
sphinx-rtd-theme	^1.0 -> ^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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Configuration

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♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

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[renovate]

⚠️ Artifact update problem

Renovate failed to update an artifact related to this branch. You probably do not want to merge this PR as-is.

♻ Renovate will retry this branch, including artifacts, only when one of the following happens:

• any of the package files in this branch needs updating, or
• the branch becomes conflicted, or
• you click the rebase/retry checkbox if found above, or
• you rename this PR's title to start with "rebase!" to trigger it manually

The artifact failure details are included below:

File name: poetry.lock

Updating dependencies
Resolving dependencies...

The "poetry.dev-dependencies" section is deprecated and will be removed in a future version. Use "poetry.group.dev.dependencies" instead.

Because no versions of sphinx-rtd-theme match >3.0.0,<3.0.1 || >3.0.1,<3.0.2 || >3.0.2,<4.0.0
 and sphinx-rtd-theme (3.0.0) depends on sphinx (>=6,<9), sphinx-rtd-theme (>=3.0.0,<3.0.1 || >3.0.1,<3.0.2 || >3.0.2,<4.0.0) requires sphinx (>=6,<9).
And because sphinx-rtd-theme (3.0.1) depends on sphinx (>=6,<9)
 and sphinx-rtd-theme (3.0.2) depends on sphinx (>=6,<9), sphinx-rtd-theme (>=3.0.0,<4.0.0) requires sphinx (>=6,<9).
So, because nextcloudappstore depends on both sphinx (^4.4) and sphinx-rtd-theme (^3.0.0), version solving failed.