Invoice tagging

[frjo]

Fixes #4874

This feature allow staff to add any invoice tags hey need in wagtail admin and then use them to tag invoices. Tags will show up on the invoice detail page and in the invoice table.

Test Steps

• That staff can add/edit invoice tags in wagtail admin
• That invoices can be tagged via modal .
• That tags show up in detail view.
• That tags show up in the invoice table.

[wes-otf]

this looks good! I think my only feedback would be that if possible it'd be awesome to get the tags on the project invoice table in the project view - do you think that'd be too crowded?

[frjo]

I will test that.

[frjo]

@wes-otf It is this table on the project detail you are thinking about?

To add the tags here I think we ned to remove something. Do both the dates need to be listed here?