"FormatException: invalid port" for HTML source

[946923759]

Describe the bug
I want to add an HTML source from a non default port, but it says this when trying to add it.

To Reproduce

1. On a computer, do python3 -m http.server or some equivalent that runs a HTTP server on a port other than 80 or 443. And have some valid files in the folder, of course.
2. Try adding it in Obtainium, in this case it was http://192.168.12.242:8000
3. Despite the HTTP server showing it was accessed, the source cannot be added

Screenshots and Logs
Oddly, the / is also missing. Changing the source to http://192.168.12.242:8000/ does not fix it.

FormatException: Invalid port (at character 23)
http://192.168.12.242:8000testApp_v10.7.52.arm64.apk
                      ^

Please complete the following information:

• Device: Surface Duo
• OS: Android 12
• Obtainium Version: 1.1.13

[946923759]

After switching to a default port, the missing / seems to be causing issues with adding the source. The HTML looks like <a href="testApp_v10.7.52.eng-arm64.apk">testApp_v10.7.52.arm64.apk</a> (no / at the beginning)

It can be solved by writing a custom index.html, at least.

[ImranR98]

https://github.com/ImranR98/Obtainium/releases/tag/v1.1.14