Bump sphinxcontrib-bibtex from 2.5.0 to 2.6.1 in /docs/sphinx (#871)

Bumps [sphinxcontrib-bibtex](https://github.com/mcmtroffaes/sphinxcontrib-bibtex) from 2.5.0 to 2.6.1.
- [Changelog](https://github.com/mcmtroffaes/sphinxcontrib-bibtex/blob/develop/CHANGELOG.rst)
- [Commits](https://github.com/mcmtroffaes/sphinxcontrib-bibtex/compare/2.5.0...2.6.1

)

---
updated-dependencies:
- dependency-name: sphinxcontrib-bibtex
  dependency-type: direct:production
  update-type: version-update:semver-minor
...
Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Sam Wu <sam.wu2@amd.com>

docs/sphinx/requirements.in

 rocm-docs-core>=0.20.0
-sphinxcontrib-bibtex==2.5.0
+sphinxcontrib-bibtex==2.6.1

docs/sphinx/requirements.txt

@@ -139,7 +139,7 @@ sphinx-notfound-page==0.8.3
     # via rocm-docs-core
 sphinxcontrib-applehelp==1.0.4
     # via sphinx
-sphinxcontrib-bibtex==2.5.0
+sphinxcontrib-bibtex==2.6.1
     # via -r requirements.in
 sphinxcontrib-devhelp==1.0.2
     # via sphinx