Remove unused swagger_auto_schema import and decorator

[Copilot]

Addresses feedback from #1: the swagger_auto_schema decorator doesn't work properly for function-based views without additional wrapper configuration.

Changes

• Remove @swagger_auto_schema(method='get') decorator from health view
• Remove unused swagger_auto_schema import

The @require_http_methods(["GET"]) decorator already restricts the endpoint to GET requests.

# Before
@require_http_methods(["GET"])
@swagger_auto_schema(method='get')  # Non-functional for FBVs
def health(request: HttpRequest):
    return HttpResponse(status=200)

# After
@require_http_methods(["GET"])
def health(request: HttpRequest):
    return HttpResponse(status=200)

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[hepheir]

swagger auto schema가 정상동작하지 않는다고 해서 제거하기보다는, 다른 방법으로 Swagger 적용이 이루어 질 수 있도록 해볼 것이기에 본 PR은 반려하겠습니다.