Update sphinx requirement from <1.7 to <6.3 (opensearch-project#374)

* Update sphinx requirement from <1.7 to <6.3

Updates the requirements on [sphinx](https://github.com/sphinx-doc/sphinx) to permit the latest version.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/master/CHANGES)
- [Commits](sphinx-doc/sphinx@0.1.61611...v6.2.0)

---
updated-dependencies:
- dependency-name: sphinx
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <support@github.com>

* Update changelog

Signed-off-by: dependabot[bot] <support@github.com>

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: dependabot[bot] <dependabot[bot]@users.noreply.github.com>
Signed-off-by: Raman Saparkhan <romasaparhan19@gmail.com>

CHANGELOG.md

@@ -16,6 +16,8 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 ### Security
 - Fixed CVE-2022-23491 reported in opensearch-dsl-py ([#295](https://github.com/opensearch-project/opensearch-py/pull/295))
 - Update ci workflows ([#318](https://github.com/opensearch-project/opensearch-py/pull/318))
+### Dependencies
+- Bumps `sphinx` from <1.7 to <6.3
 
 ## [2.2.0]
 ### Added
@@ -79,4 +81,4 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 [2.0.1]: https://github.com/opensearch-project/opensearch-py/compare/v2.0.0...v2.0.1
 [2.1.0]: https://github.com/opensearch-project/opensearch-py/compare/v2.0.1...v2.1.0
 [2.1.1]: https://github.com/opensearch-project/opensearch-py/compare/v2.1.0...v2.1.1
-[2.2.0]: https://github.com/opensearch-project/opensearch-py/compare/v2.1.1...v2.2.0
+[2.2.0]: https://github.com/opensearch-project/opensearch-py/compare/v2.1.1...v2.2.0

dev-requirements.txt

@@ -3,7 +3,7 @@ pytest
 pytest-cov
 coverage
 mock
-sphinx<1.7
+sphinx<6.3
 sphinx_rtd_theme
 jinja2