[BUGFIX] Redirect slash when defining ARGILLA_BASE_URL (#5796)

# Description
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Closes #5792

**Type of change**
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- Bug fix (non-breaking change which fixes an issue)

**How Has This Been Tested**
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- I added relevant documentation
- I followed the style guidelines of this project
- I did a self-review of my code
- I made corresponding changes to the documentation
- I confirm My changes generate no new warnings
- I have added tests that prove my fix is effective or that my feature
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argilla-server/src/argilla_server/_app.py

@@ -171,7 +171,7 @@ def create_server_app() -> FastAPI:
     # This if-else clause is needed to simplify the test dependency setup. Otherwise, we cannot override dependencies
     # easily. We can review this once we have separate fastapi application for the api and the webapp.
     if settings.base_url and settings.base_url != "/":
-        _app = FastAPI(docs_url=None, redoc_url=None, openapi_url=None, redirect_slashes=False)
+        _app = FastAPI(docs_url=None, redoc_url=None, openapi_url=None, redirect_slashes=True)
         _app.mount(settings.base_url, app)
         return _app
     else: