fix: Truncate python3 version to simplify symlink logic (#19)

* Instead of attempting to capture the minor version number just symlink to python3. This allows
for "${which_python::-1}" to easily resolve to 'python'.
* Amends PR #18

install_python.sh

@@ -80,7 +80,7 @@ function symlink_python_to_python3 {
     local python_version
     python_version="$(python3 --version)"
     local which_python
-    which_python="$(command -v python3)${python_version:8:2}"
+    which_python="$(command -v python3)${python_version:8:}"
     local which_pip
     which_pip="$(command -v pip3)"