[IMP]fastapi: enable multi-slash routes

Author: PicchiSeba

fastapi/demo/fastapi_endpoint_demo.xml

@@ -44,4 +44,15 @@ methods. See documentation to learn more about how to create a new app.
     <field name="demo_auth_method">http_basic</field>
       <field name="user_id" ref="my_demo_app_user" />
   </record>
+
+  <record id="fastapi_endpoint_multislash_demo" model="fastapi.endpoint">
+    <field name="name">Fastapi Multi-Slash Demo Endpoint</field>
+    <field name="description">
+        Like the other demo endpoint but with multi-slash
+    </field>
+    <field name="app">demo</field>
+    <field name="root_path">/fastapi/demo</field>
+    <field name="demo_auth_method">http_basic</field>
+    <field name="user_id" ref="my_demo_app_user" />
+  </record>
 </odoo>

fastapi/tests/__init__.py

@@ -1,2 +1,3 @@
 from . import test_fastapi
 from . import test_fastapi_demo
+from . import test_fastapi_multislash_demo

fastapi/tests/test_fastapi_multislash_demo.py

@@ -0,0 +1,32 @@
+# License LGPL-3.0 or later (http://www.gnu.org/licenses/LGPL).
+
+
+from requests import Response
+
+from fastapi import status
+
+from ..routers import demo_router
+from .common import FastAPITransactionCase
+
+
+class FastAPIMultiSlashDemoCase(FastAPITransactionCase):
+    """
+    This test verifies that multi-slash endpoint are properly reached
+    """
+
+    @classmethod
+    def setUpClass(cls) -> None:
+        super().setUpClass()
+        cls.default_fastapi_router = demo_router
+        cls.default_fastapi_running_user = cls.env.ref(
+            "fastapi.fastapi_endpoint_multislash_demo"
+        )
+        cls.default_fastapi_authenticated_partner = cls.env["res.partner"].create(
+            {"name": "FastAPI Demo"}
+        )
+
+    def test_hello_world(self) -> None:
+        with self._create_test_client() as test_client:
+            response: Response = test_client.get("/demo/")
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        self.assertDictEqual(response.json(), {"Hello": "World"})