build(deps): Bump orjson from 3.9.5 to 3.9.15

Bumps [orjson](https://github.com/ijl/orjson) from 3.9.5 to 3.9.15.
- [Release notes](https://github.com/ijl/orjson/releases)
- [Changelog](https://github.com/ijl/orjson/blob/master/CHANGELOG.md)
- [Commits](ijl/orjson@3.9.5...3.9.15)

---
updated-dependencies:
- dependency-name: orjson
  dependency-type: indirect
...

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

Author: dependabot[bot]

requirements.txt

@@ -89,7 +89,7 @@ odfpy==1.4.1
     # via flattentool
 openpyxl==3.0.7
     # via flattentool
-orjson==3.9.5
+orjson==3.9.15
     # via libcoveoc4ids
 persistent==4.7.0
     # via

requirements_dev.txt

@@ -170,7 +170,7 @@ openpyxl==3.0.7
     # via
     #   -r requirements.txt
     #   flattentool
-orjson==3.9.5
+orjson==3.9.15
     # via
     #   -r requirements.txt
     #   libcoveoc4ids