Dutch Outlook installation instructions use incorrect labels

[rubenhensen]

The Dutch localization of the installation guide uses terminology that does not match the current Outlook UI.
* Current: "Onder aangepaste add-ins, klik op 'Een aangepaste add-in toevoegen' en vervolgens op 'Toevoegen vanuit bestand...'"
* Corrected: "Onder 'Mijn invoegtoepassingen', klik op 'Aangepaste invoegtoepassing toevoegen' en vervolgens op 'Toevoegen uit bestand'"

[rubenhensen]

/dobby fix this issue, there are other dobbies also working, so make sure the PR has not conflicts

[dobby-coder]

Dobby sees the request! Dobby will fix the Dutch Outlook installation labels right away, sir! Dobby will also be very careful to not conflict with the other helpers working on this repo!

[dobby-coder]

Already shipped via #204 (merged 2026-05-08). Verified the relevant fix is on main. Safe to close.

[dobby-coder]

Resolved by #204 (consolidated addon install-doc, i18n & UI fixes). The original sub-PR for this issue was rolled into that consolidation, but the closing keyword didn't propagate, so closing manually.