build(deps): Bump sphinx from 5.2.3 to 5.3.0 in /requirements (#37)

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 5.2.3 to 5.3.0.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/master/CHANGES)
- [Commits](sphinx-doc/sphinx@v5.2.3...v5.3.0)

---
updated-dependencies:
- dependency-name: sphinx
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Matt Robinson <[email protected]>

Author: dependabot[bot]

requirements/build.txt

@@ -20,8 +20,6 @@ idna==3.4
     # via requests
 imagesize==1.4.1
     # via sphinx
-importlib-metadata==5.0.0
-    # via sphinx
 jinja2==3.1.2
     # via sphinx
 markupsafe==2.1.1
@@ -38,12 +36,12 @@ requests==2.28.1
     # via sphinx
 snowballstemmer==2.2.0
     # via sphinx
-sphinx==5.2.3
+sphinx==5.3.0
     # via
-    #   -r requirements/build.in
+    #   -r build.in
     #   sphinx-rtd-theme
 sphinx-rtd-theme==1.0.0
-    # via -r requirements/build.in
+    # via -r build.in
 sphinxcontrib-applehelp==1.0.2
     # via sphinx
 sphinxcontrib-devhelp==1.0.2
@@ -58,5 +56,3 @@ sphinxcontrib-serializinghtml==1.1.5
     # via sphinx
 urllib3==1.26.12
     # via requests
-zipp==3.9.0
-    # via importlib-metadata