[Bug] Python Azure Function worker incorrectly URL encodes cookie value

### Expected Behavior

Azure Function worker using Python FastAPI should not URL encode cookie values

Expected behavior on HTTP Response Headers:
`set-cookie: test="hello//world"; Path=/; SameSite=lax`

e.g. when using Python FastAPI without Azure Functions, it correctly does not URL encode.
````
import uvicorn
from fastapi import FastAPI
from fastapi.responses import PlainTextResponse

app = FastAPI()

@app.get("/")
def http_trigger():
response = PlainTextResponse("", status_code=200)
response.set_cookie(key='test', value='hello//world')

return response

if __name__ == "__main__":
uvicorn.run(app, host="127.0.0.1", port=7071)

````

Run `curl -v http://localhost:7071/` and response is correct as `set-cookie: test="hello//world"; Path=/; SameSite=lax`

### Actual Behavior

Actual incorrect behavior on HTTP Response Headers, cookie value is incorrect and unexpectedly URL encoded

`Set-Cookie: test=hello%2F%2Fworld; domain=; path=/; samesite=lax`

Tested bug with
* Python 3.12 with FastAPI
* Azure Functions Core tools 4.3.0 locally
* Deployed to production Azure Function

### Steps to Reproduce

1. Run `func start` or deploy to Azure using sample code provided below
2. Send a test HTTP request e.g. `curl -v http://localhost:7071/`
3. Azure Functions worker incorrectly URL encodes the response cookie value in the `Set-Cookie` header

### Relevant code being tried

```shell
import azure.functions as func
from fastapi import FastAPI
from fastapi.responses import PlainTextResponse

app = FastAPI()
func_app = func.AsgiFunctionApp(app=app, http_auth_level=func.AuthLevel.ANONYMOUS)

@app.get("/")
def http_trigger():

response = PlainTextResponse("", status_code=200)
response.set_cookie(key='test', value='hello//world')

return response
```

### Relevant log output

```shell
N/A
```

### requirements.txt file

```shell
azure-functions
fastapi
```

### Where are you facing this problem?

Production Environment (explain below)

### Function app name

Private

### Additional Information

_No response_

func.AsgiFunctionApp によって作成された ASGI アダプターのパスから始め、そのレスポンスヘッダー処理を FastAPI の PlainTextResponse.set_cookie の出力と比較します。値 hello//world を使って func start と curl -v で再現します。Set-Cookie ヘッダーが期待される Cookie 値を保持し、回帰チェックでカバーされれば完了です。

索引モデルが issue の本文から書いたものです。