/bin/sh: 0: Illegal option - when installing ppa:deadsnakes/ppa on ubuntu container

I am stumbling on this issue:Why cannot add PPA deadsnakes?This line in my dockerfile:

RUN add-apt-repository ppa:deadsnakes/ppa

Failing my docker build with:

1.028 Cannot add PPA: 'ppa:~deadsnakes/ubuntu/ppa'.1.028 ERROR: '~deadsnakes' user or team does not exist.

So I did what the answer was from the other SO-question:

# Define the base imageFROM ubuntu:20.04 AS builder-image# avoid stuck build due to user promptARG DEBIAN_FRONTEND=noninteractiveRUN apt-get update && \    apt-get install -y software-properties-common && \    rm -rf /var/lib/apt/lists/*RUN add-apt-repository universe RUN add-apt-repository restrictedRUN -E add-apt-repository -y 'ppa:deadsnakes/ppa'

Giving me following error:

 => => transferring context: 6.70kB                                                                                                                    0.3s------> [airflow-webserver  5/26] RUN -E add-apt-repository -y 'ppa:deadsnakes/ppa':0.341 /bin/sh: 0: Illegal option -------failed to solve: process "/bin/sh -c -E add-apt-repository -y 'ppa:deadsnakes/ppa'" did not complete successfully: exit code: 2

Does anyone know how i can get my way around this? Thank you in advance