sanitize the url of the endpoint

[OniriCorpe]

Describe the bug I scanned the fluent reader qrcode to get my RSS with fluent reader lite on my ipad and it gave me a network error in the end there were spaces before the URL, after removing the spaces the connection worked

To Reproduce Steps to reproduce the behavior:

1. have spaces before the URL in fluent reader (which works)
2. scan the qrcode from fluent reader with the ipad camera
3. import the configuration into fluent reader lite
4. See a network error message

Expected behavior that the software sanitizes the entries and consequently deletes the spaces

Platform (please complete the following information):

• OS: iPadOS v16.1.1
• Fluent Reader Lite v1.0.3