fix email sending bug (#3169)

* fix email sending bug

Mail sending in the current version of django has a bug with some versions of python. 3.8 should be compatible.

See django/django#17979 (comment)

* fix wrong version

* Update Dockerfile

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Co-authored-by: Henrik Hørlück Berg <henrik@horluck.no>

Dockerfile

@@ -41,7 +41,7 @@ COPY --from=js-static $APP_DIR/bundles ./bundles
 
 RUN ./manage.py collectstatic
 
-FROM amazon/aws-lambda-python:3.11
+FROM amazon/aws-lambda-python:3.11.2024.03.28.16
 
 LABEL maintainer="Dotkom <dotkom@online.ntnu.no>"
 ENV POETRY_VIRTUALENVS_CREATE=false \