Add missing '--no-cache-dir' in 1.10.12 alpine image (#230)

1.10.12 alpine image missed `--no-cache-dir`, hence the final docker image was big.

This commit adds it back to pip install command

1.10.12/alpine3.10/Dockerfile

@@ -93,7 +93,7 @@ RUN echo https://github.com/astronomer/ap-airflow/raw/${REPO_BRANCH}/alpine-pack
 	&& update-ca-certificates \
 	&& cp /usr/share/zoneinfo/UTC /etc/localtime \
 	&& pip3 install --no-cache-dir --upgrade snowflake-connector-python==1.9.1 \
-	&& pip3 install "${AIRFLOW_MODULE}" --constraint "https://raw.githubusercontent.com/apache/airflow/constraints-${AIRFLOW_VERSION}/constraints-3.7.txt" \
+	&& pip3 install --no-cache-dir "${AIRFLOW_MODULE}" --constraint "https://raw.githubusercontent.com/apache/airflow/constraints-${AIRFLOW_VERSION}/constraints-3.7.txt" \
 	&& pip3 install --no-cache-dir "https://github.com/astronomer/astronomer-airflow-scripts/releases/download/v0.0.5/astronomer_airflow_scripts-0.0.5-py3-none-any.whl" \
 	&& pip3 install --no-cache-dir "astronomer-fab-security-manager~=1.2, >=1.2.2" \
 	&& apk del .build-deps py3-numpy-dev \