DocumentHandler: infoclick buttons that link to a document can reload the app

[jacobwod]

Describe the bug
An issue with DocumentHandler buttons in infoclick was just discovered. As of #1252, Hajk listens to change of the query string parameter of URL (everything after #). If that string changes, Hajk acts upon those changes (see #1252 for a list of parameters it looks for).

Now, DocumentHandler can produce infoclick buttons using the {foobar}@@documenthandler notation.

The problem is that currently the HTML element produced by this function is an anchor with a href value of "#". Clicking such a button changes the value of the query string, which in turns leads to new params being parsed by Hajk as of #1252.

But since the string is empty and it specifically lacks the m parameter, Hajk interprets this as a change of map from whatever the current value is to the default one.

Since a change of map config involves app reload, this is what happens:

Skarminspelning.2023-06-05.kl.14.59.10.mov

A better behaviour would be something like this:

Skarminspelning.2023-06-05.kl.14.58.42.mov

There's a small detail though: we don't want to change from A to BUTTON, since they render differently.

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This portion of code looks a bit funny too:

We want to render a BUTTON when not printing. But we provide a value for href attribute and the MUI docs says that:

The URL to link to when the button is clicked. If defined, an a element will be used as the root node.

So this hard-coded href value made this to always render as an A element (except print mode) and never a BUTTON.

Proposed solution
I think I'll keep the element but remove the attribute to eliminate the query string change.