GHSA-w466-2wfc-8g58: Open WebUI has vulnerable dependency on starlette via fastapi

In version 0.3.32 of open-webui, the application uses a vulnerable version of the starlette package through its dependency on fastapi. The starlette package versions <=0.49 are susceptible to uncontrolled resource consumption, which can be exploited to cause a denial of service through memory exhaustion. This issue is addressed in fastapi version 0.115.3.