2017 Portugal Euro Ten Cent - Dot In Date?

Coin: 2017 Euro ten cent from Portugal, second map, KM# 763, Schon # 282, Numista # 9895.

I'm not quite sure what, if anything, this might be. It is a common, average circulated 2017 Euro ten cent from Portugal. There is a pronounced "dot" to the left of the 7 in the date. The "dot" has a roughly triangular shape, and is raised on the coin surface. Other 2017 examples do not have this dot. My best guess is that it could be a die hardness test mark. Are die hardness tests done for Euro coin production dies at the Impresa Nacional - Casa de la Moeda? Thoughts?

Here are the full obverse and reverse photos of this coin.



Here are the date detail and a closeup of the "dot."



Here is the date detail of a normal 2017 Portugal Euro ten cent for comparison.