fix(Tabset): reset tabset to current tab when first tab is removed

[jav7zaid]

Description

Tabset is not resetting back, when first tab is removed.

What are the relevant story cards/tickets? Any additional PRs or other references?

#872
Jira:

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[nicko-winner]

what is the advantage of to adding a tab size as an attribute? I wonder if the hx-tabset component could/should/can be aware of how many tabs it has.

Side note: tabCount, might be a more descriptive name as "size" might imply "small, medium, large" etc, related to a component.