Some Footer links open new window

[danielpeintner]

In WoT website work, we got the feedback that from accessibility point of view one should not open new windows/tabs when clicking on (even external) links.

Docusaurus default configuration seems to open new window/tab for external links.
Can be seen in our footer

@egekorkan @SergioCasCeb and I took a quick look but weren't able to fix it in the call.
We need to take a closer look...