build(NoTicket): update sphinx-rtd-theme requirement

Updates the requirements on [sphinx-rtd-theme](https://github.com/readthedocs/sphinx_rtd_theme) to permit the latest version.
- [Changelog](https://github.com/readthedocs/sphinx_rtd_theme/blob/master/docs/changelog.rst)
- [Commits](readthedocs/sphinx_rtd_theme@2.0.0rc1...3.0.2)

---
updated-dependencies:
- dependency-name: sphinx-rtd-theme
  dependency-version: 3.0.2
  dependency-type: direct:production
...

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

Author: dependabot[bot]

setup.cfg

@@ -68,7 +68,7 @@ dev =
     types-cryptography==3.3.18
 docs =
     sphinx==7.*
-    sphinx-rtd-theme==2.*
+    sphinx-rtd-theme>=2,<4
 
 [options.package_data]
 firebolt = py.typed