Update Dockerfile

Dockerfile

@@ -2,7 +2,7 @@ FROM python:3.7-slim as base-image
 ARG POETRY_VERSION=1.1.7
 WORKDIR /service
 RUN pip install "poetry==$POETRY_VERSION"
-ADD pyproject.toml poetry.lock readme.md ./
+ADD pyproject.toml poetry.lock README.md ./
 ADD makeqr makeqr
 RUN poetry build
 RUN python -m venv .venv