Do not send empty data to `StreamingResponse` on `BaseHTTPMiddleware` (#1609)
Do not send empty data to `StreamingResponse` on `BaseHTTPMiddleware` (#1609)

Co-authored-by: Adrian Garcia Badaracco <e27daa303f2cab77ffec56a54997f382ae605c48@users.noreply.github.com>
Co-authored-by: Tom Christie <96835dd8bfa718bd6447ccc87af89ae1675daeca@tomchristie.com>
encode/starlette,encode/starlette