docs(python): add docs for new_context fixture (#30522)

https://github.com/microsoft/playwright-internal/issues/202

docs/src/test-runners-python.md

@@ -55,6 +55,7 @@ def test_my_app_is_working(fixture_name):
 
 - `context`: New [browser context](./browser-contexts) for a test.
 - `page`: New [browser page](./pages) for a test.
+- `new_context`: Allows creating different [browser contexts](./browser-contexts) for a test. Useful for multi-user scenarios. Accepts the same parameters as [`method: Browser.newContext`].
 
 **Session scope**: These fixtures are created when requested in a test function and destroyed when all tests end.
 
@@ -211,30 +212,6 @@ def browser_context_args(browser_context_args, playwright):
 
 Or via the CLI `--device="iPhone 11 Pro"`
 
-### Persistent context
-
-```py title="conftest.py"
-import pytest
-from playwright.sync_api import BrowserType
-from typing import Dict
-
-@pytest.fixture(scope="session")
-def context(
-    browser_type: BrowserType,
-    browser_type_launch_args: Dict,
-    browser_context_args: Dict
-):
-    context = browser_type.launch_persistent_context("./foobar", **{
-        **browser_type_launch_args,
-        **browser_context_args,
-        "locale": "de-DE",
-    })
-    yield context
-    context.close()
-```
-
-When using that all pages inside your test are created from the persistent context.
-
 ### Using with `unittest.TestCase`
 
 See the following example for using it with `unittest.TestCase`. This has a limitation,