Ability to Refresh only TabItem (without Refreshing its content)

[matwachich]

Checklist

• I have searched the issue tracker for open issues that relate to the same feature, before opening a new one.
• This issue only relates to a single feature. I will open new issues for any other features.

Is your feature request related to a problem?

Sometimes I need to update TabItem title and/or icon (updating items count for example...).
But when calling app_or_docTab.Refresh, this will trigger refreshing of all tabs contents (wich is not desired because very heavy operation).

Is it possible to construct a solution with the existing API?

Not really...

Describe the solution you'd like to see.

app/docTab.Refresh => will refresh only tab items
app/docTab.RefreshContent => will refresh all tabs contents

or

app/docTab.Refresh => keeps current behaviour
app/docTab.RefreshTabs or Items => refresh only tab items

why not also:
app/docTab.SetItem(title string, icon fyne.Resource) (see #1289)

app/docTab.RefreshItem(ti *container.TabItem, refreshContent bool)
app/docTab.RefreshItemIndex(id int, refreshContent bool)