Merge pull request #7 from hvalev/dependabot/docker/python-3.9.4-alpine3.12

Bump python from 3.9.2-alpine3.12 to 3.9.4-alpine3.12

Dockerfile

@@ -1,4 +1,4 @@
-FROM python:3.9.2-alpine3.12
+FROM python:3.9.4-alpine3.12
 COPY requirements.txt dht22mqtt.py gpiomapping.py ./
 RUN apk add gcc musl-dev && \
     pip3 install -r requirements.txt --no-cache-dir && \