test: remove warnings for TemplateResponse (#2368)

* test: remove warnings for `TemplateResponse`
removes warnings
```
tests/core/views/test_generic.py::test_core_views_generic
tests/core/views/test_generic.py::test_get_wallet_with_user_and_wallet
tests/core/views/test_generic.py::test_get_extensions
tests/core/views/test_public_api.py::test_core_views_generic
  /home/dni/.cache/pypoetry/virtualenvs/lnbits-XeqO4Z-j-py3.10/lib/python3.10/site-packages/starlette/templating.py:178: DeprecationWarning: The `name` is not the first para
meter anymore. The first parameter should be the `Request` instance.
  Replace `TemplateResponse(name, {"request": request})` by `TemplateResponse(request, name)`.
    warnings.warn(
```

lnbits/app.py

@@ -497,7 +497,7 @@ def register_exception_handlers(app: FastAPI):
             and "text/html" in request.headers["accept"]
         ):
             return template_renderer().TemplateResponse(
-                "error.html", {"request": request, "err": f"Error: {str(exc)}"}
+                request, "error.html", {"err": f"Error: {str(exc)}"}
             )
 
         return JSONResponse(
@@ -519,8 +519,9 @@ def register_exception_handlers(app: FastAPI):
             and "text/html" in request.headers["accept"]
         ):
             return template_renderer().TemplateResponse(
+                request,
                 "error.html",
-                {"request": request, "err": f"Error: {str(exc)}"},
+                {"err": f"Error: {str(exc)}"},
             )
 
         return JSONResponse(
@@ -547,6 +548,7 @@ def register_exception_handlers(app: FastAPI):
                 return response
 
             return template_renderer().TemplateResponse(
+                request,
                 "error.html",
                 {
                     "request": request,