Inconsistent headers in modals

[LeXofLeviafan]

Bootstrap4 modals have a minor bug, which is still present in the current version of the repo. Namely, both model/modals/edit.html and model/modals/create.html contain the following code in header_text block:

<h5 class="modal-title">{{ … }}</h5>

Meanwhile, model/modals/details.html contains the following instead:

<h3>{{ … }}</h3>

…Which as you might guess results in different styling: