Update fastapi requirement from ^0.111.0 to ^0.115.4

Updates the requirements on [fastapi](https://github.com/fastapi/fastapi) to permit the latest version.
- [Release notes](https://github.com/fastapi/fastapi/releases)
- [Commits](fastapi/fastapi@0.111.0...0.115.4)

---
updated-dependencies:
- dependency-name: fastapi
  dependency-type: direct:production
...

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

pyproject.toml

@@ -7,7 +7,7 @@ readme = "README.md"
 
 [tool.poetry.dependencies]
 python = "^3.11"
-fastapi = {extras = ["uvicorn"], version = "^0.111.0"}
+fastapi = {extras = ["uvicorn"], version = "^0.115.4"}
 python-multipart = "^0.0.9"
 jinja2 = "^3.1.4"
 itsdangerous = "^2.2.0"