tests: Allow to set Python interpreter to be used by Ansible

On some systems it is required or desired to run Ansible with a specific
Python interpreter. This patch allows the selection of the Python binary
to use for the pytest playbook tests by setting the environment variable
IPA_PYTHON_PATH. Set it the the full path of the Python interpreter.

tests/README.md

@@ -36,6 +36,12 @@ environment variable. For example:
 IPA_SSH_PASSWORD=<ipaserver_ssh_password> IPA_SERVER_HOST=<ipaserver_host_or_ip> pytest
 ```
 
+If you want, or need to to set the Python interpreter to use, you must set `IPA_PYTHON_PATH`
+environment variable. For example:
+
+```
+IPA_PYTHON_PATH=/usr/bin/python3.14 IPA_SERVER_HOST=<ipaserver_host_or_ip> pytest
+```
 
 To run a single test use the full path with the following format:
 

tests/utils.py

@@ -43,6 +43,10 @@ def get_ssh_password():
     return os.getenv("IPA_SSH_PASSWORD")
 
 
+def get_python_interpreter():
+    return os.getenv("IPA_PYTHON_PATH")
+
+
 def get_server_host():
     return os.getenv("IPA_SERVER_HOST")
 
@@ -97,6 +101,12 @@ def get_inventory_content():
     if sshpass:
         ipa_server_host += " ansible_ssh_pass=%s" % sshpass
 
+    python_interpreter = get_python_interpreter()
+    if python_interpreter:
+        ipa_server_host += (
+            " ansible_python_interpreter=%s" % python_interpreter
+        )
+
     lines = [
         "[ipaserver]",
         ipa_server_host,