Allow transport override on winrm backend

doc/source/backends.rst

@@ -178,6 +178,7 @@ The winrm backend uses `pywinrm <https://pypi.python.org/pypi/pywinrm>`_::
 
     $ py.test --hosts='winrm://Administrator:Password@127.0.0.1'
     $ py.test --hosts='winrm://vagrant@127.0.0.1:2200?no_ssl=true&no_verify_ssl=true'
+    $ py.test --hosts='winrm://vagrant@127.0.0.1:2200?no_ssl=true&no_verify_ssl=true&transport=plaintext'
 
 pywinrm's default read and operation timeout can be overridden using query
 arguments ``read_timeout_sec`` and ``operation_timeout_sec``::

testinfra/backend/__init__.py

@@ -64,6 +64,7 @@ def parse_hostspec(hostspec: str) -> tuple[str, dict[str, Any]]:
             "controlpersist",
             "kubeconfig",
             "context",
+            "transport",
         ):
             if key in query:
                 kw[key] = query[key][0]

testinfra/backend/winrm.py

@@ -56,6 +56,7 @@ def __init__(
         no_verify_ssl: bool = False,
         read_timeout_sec: Optional[int] = None,
         operation_timeout_sec: Optional[int] = None,
+        transport: str = None,
         *args: Any,
         **kwargs: Any,
     ):
@@ -66,7 +67,7 @@ def __init__(
                 self.host.name,
                 ":{}".format(self.host.port) if self.host.port else "",
             ),
-            "transport": "ntlm",
+            "transport": transport or "ntlm",
             "username": self.host.user,
             "password": self.host.password,
         }