Add Gitea & Forgejo Instance & Username Field in users bio

[trymeouteh]

You can add a Github username in your username bio. Please add fields to add your Gitea and Forgejo instance and username in your weblate account bio.

[nijel]

It doesn't make sense to ask for username in that case as that needs full URL to include server as well. And there is already a field for that in the profile:

weblate/weblate/accounts/models.py

Lines 564 to 570 in 21ff9e8

	codesite = models.URLField(
	verbose_name=gettext_lazy("Code site URL"),
	blank=True,
	help_text=gettext_lazy(
	"Link to your code profile for services like Codeberg or GitLab."
	),
	)