build(deps): bump sphinx-scylladb-theme from 1.8.3 to 1.8.4 in /docs

Bumps [sphinx-scylladb-theme](https://github.com/scylladb/sphinx-scylladb-theme) from 1.8.3 to 1.8.4.
- [Release notes](https://github.com/scylladb/sphinx-scylladb-theme/releases)
- [Commits](scylladb/sphinx-scylladb-theme@1.8.3...1.8.4)

---
updated-dependencies:
- dependency-name: sphinx-scylladb-theme
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

docs/poetry.lock

@@ -8,7 +8,7 @@ package-mode = false
 [tool.poetry.dependencies]
 python = "^3.10"
 pygments = "^2.18.0"
-sphinx-scylladb-theme = "^1.8.1"
+sphinx-scylladb-theme = "^1.8.4"
 myst-parser = "^3.0.1"
 sphinx-autobuild = "^2024.4.19"
 Sphinx = "^7.3.7"