Fix bug with old PyBaMM version being fetched for scheduled tests (#572)

* Sort the releases before saving to a variable

* Update rc command as well

scripts/ci/build_matrix.sh

@@ -12,10 +12,10 @@
 python_version=("3.9" "3.10" "3.11" "3.12")
 os=("ubuntu-latest" "windows-latest" "macos-13" "macos-14")
 # This command fetches the last PyBaMM version excluding release candidates from PyPI
-pybamm_version=($(curl -s https://pypi.org/pypi/pybamm/json | jq -r '.releases | keys[]' | grep -v rc | tail -n 1 | paste -sd " " -))
+pybamm_version=($(curl -s https://pypi.org/pypi/pybamm/json | jq -r '.releases | keys[]' | grep -v rc | sort -V | tail -n 1 | paste -sd " " -))
 
 # This command fetches the last PyBaMM versions including release candidates from PyPI
-#pybamm_version=($(curl -s https://pypi.org/pypi/pybamm/json | jq -r '.releases | keys[]' | tail -n 1 | paste -sd " " -))
+#pybamm_version=($(curl -s https://pypi.org/pypi/pybamm/json | jq -r '.releases | keys[]' | sort -V | tail -n 1 | paste -sd " " -))
 
 # open dict
 json='{