CI: migrate pypy3 tests from bionic to Arch

The bionic image is really old and mainly exists to test that Meson
itself still works on really old distros (and really old python).
Ideally we'd avoid depending too much on it.

We can get a very modern pypy3 automatically this way, and potentially
use it for more stuff too.

ci/ciimage/arch/install.sh

@@ -7,7 +7,7 @@ source /ci/common.sh
 # Inspired by https://github.com/greyltc/docker-archlinux-aur/blob/master/add-aur.sh
 
 pkgs=(
-  python python-pip
+  python python-pip pypy3
   ninja make git sudo fakeroot autoconf automake patch
   libelf gcc gcc-fortran gcc-objc vala rust bison flex cython go dlang-dmd
   mono boost qt5-base gtkmm3 gtest gmock protobuf gobject-introspection

ci/ciimage/bionic/install.sh

@@ -58,22 +58,6 @@ update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.7 2 \
 
 python3 -m pip install -U "${base_python_pkgs[@]}" "${python_pkgs[@]}"
 
-pushd /opt
-# Download and install PyPy3.8, and link it to /usr/bin/pypy3
-# At some point it would be more robust to download and parse
-# https://downloads.python.org/pypy/versions.json
-wget https://downloads.python.org/pypy/pypy3.8-v7.3.9-linux64.tar.bz2
-pypy_sha256="08be25ec82fc5d23b78563eda144923517daba481a90af0ace7a047c9c9a3c34"
-if [ $pypy_sha256 != $(sha256sum pypy3.8-v7.3.9-linux64.tar.bz2 | cut -f1 -d" ") ]; then
-  echo bad sha256 for PyPy
-  exit -1
-fi
-tar -xf pypy3.8-v7.3.9-linux64.tar.bz2
-pypy3.8-v7.3.9-linux64/bin/pypy3 -m ensurepip
-popd
-ln -s /opt/pypy3.8-v7.3.9-linux64/bin/pypy3 /usr/bin/pypy3
-
-
 # Install the ninja 0.10
 wget https://github.com/ninja-build/ninja/releases/download/v1.10.0/ninja-linux.zip
 unzip ninja-linux.zip -d /ci