[ci] Use Python 3.9 in CI for newer fusesoc

Signed-off-by: Alexander Williams <[email protected]>

Author: a-will

apt-requirements.txt

@@ -40,11 +40,11 @@ ninja-build
 openssl
 perl
 pkgconf
-python3
 python3-pip
 python3-setuptools
 python3-urllib3
 python3-wheel
+python3.9-full
 srecord
 tree
 xsltproc

ci/install-package-dependencies.sh

@@ -81,7 +81,9 @@ xargs sudo $APT_CMD install -y <"$ci_reqs"
 # appropriate bin directory to the PATH
 export PATH=$HOME/.local/bin:$PATH
 
-python3 -m pip install --user -r python-requirements.txt --require-hashes
+python3.9 -m venv $HOME/ot-python
+source $HOME/ot-python/bin/activate
+python3 -m pip install -r python-requirements.txt --require-hashes
 
 # Install Verible
 lsb_sr="$(lsb_release -sr)"