chore(ci): pin pyenv version (#3228)

Co-authored-by: Gabriele N. Tornetta <[email protected]>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Author: 3 people

Dockerfile.buster

@@ -64,7 +64,7 @@ ENV PYENV_ROOT /root/.pyenv
 ENV PATH ${PYENV_ROOT}/shims:${PYENV_ROOT}/bin:$PATH
 
 # Install pyenv
-RUN git clone git://github.com/pyenv/pyenv.git "${PYENV_ROOT}"
+RUN git clone --depth 1 --branch v2.2.4 git://github.com/pyenv/pyenv.git "${PYENV_ROOT}"
 
 
 # Install all required python versions