Bump sphinxcontrib-bibtex from 2.6.2 to 2.6.3 in /docs/sphinx (#1511)

Bumps [sphinxcontrib-bibtex](https://github.com/mcmtroffaes/sphinxcontrib-bibtex) from 2.6.2 to 2.6.3.
- [Changelog](https://github.com/mcmtroffaes/sphinxcontrib-bibtex/blob/develop/CHANGELOG.rst)
- [Commits](https://github.com/mcmtroffaes/sphinxcontrib-bibtex/compare/2.6.2...2.6.3

)

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

docs/sphinx/requirements.in

 rocm-docs-core==1.7.2
-sphinxcontrib-bibtex==2.6.2
+sphinxcontrib-bibtex==2.6.3

docs/sphinx/requirements.txt

@@ -137,7 +137,7 @@ sphinx-notfound-page==1.0.3
     # via rocm-docs-core
 sphinxcontrib-applehelp==2.0.0
     # via sphinx
-sphinxcontrib-bibtex==2.6.2
+sphinxcontrib-bibtex==2.6.3
     # via -r requirements.in
 sphinxcontrib-devhelp==2.0.0
     # via sphinx