submodules with relative paths link to wrong place in web UI

Summary

When a submodule is created with a relative path, it links to example.com/examplesubmodulename instead of example.com/examplenamespace/examplesubmodulename

Steps to reproduce

Create a .gitmodules file in someothermodule located at example.com/examplenamespace/someothermodule as follows:

[submodule "examplesubmodulename"]
	path = examplesubmodulename
	url = ../examplesubmodulename

Expected behavior

Clicking on examplesubmodulename when browsing the repository at example.com/examplenamespace/someothermodule brings me to example.com/examplenamespace/examplesubmodulename

Actual behavior

Clicking on examplesubmodulename when browsing the repository at example.com/examplenamespace/someothermodule brings me to example.com/examplesubmodulename

Output of checks

This bug happens on GitLab.com