Tests, WebHost: add tests for host_room and minor cleanup (#3619)

* Tests, WebHost: move out setUp and fix typing in api_generate

Also fixes a typo
and changes client to be per-test rather than a ClassVar

* Tests, WebHost: add tests for display_log endpoint

* Tests, WebHost: add tests for host_room endpoint

* Tests, WebHost: enable Flask DEBUG mode for tests

This provides the actual error if a test raised an exception on the server.

* Tests, WebHost: use user_path for logs

This is what custom_server does now.

* Tests, WebHost: avoid triggering security scans

test/webhost/__init__.py

@@ -0,0 +1,36 @@
+import unittest
+import typing
+from uuid import uuid4
+
+from flask import Flask
+from flask.testing import FlaskClient
+
+
+class TestBase(unittest.TestCase):
+    app: typing.ClassVar[Flask]
+    client: FlaskClient
+
+    @classmethod
+    def setUpClass(cls) -> None:
+        from WebHostLib import app as raw_app
+        from WebHost import get_app
+
+        raw_app.config["PONY"] = {
+            "provider": "sqlite",
+            "filename": ":memory:",
+            "create_db": True,
+        }
+        raw_app.config.update({
+            "TESTING": True,
+            "DEBUG": True,
+        })
+        try:
+            cls.app = get_app()
+        except AssertionError as e:
+            # since we only have 1 global app object, this might fail, but luckily all tests use the same config
+            if "register_blueprint" not in e.args[0]:
+                raise
+            cls.app = raw_app
+
+    def setUp(self) -> None:
+        self.client = self.app.test_client()