COPENHAGEN (Reuters) – Denmark will hold a vote this year on whether to begin participating in a common European Union defence policy following Russia’s invasion of Ukraine, almost 30 years after Danes chose to opt out, Danish news outlets reported on Sunday. Since Russian President Vladimir Putin launched what he calls a special military operation in Ukraine, Danish lawmakers have called for Denmark to hike its defence budget and to quit the opt-out from the EU’s Common Security and Defence Policy (CSDP). Participating in the CSDP would enable Denmark to take part in joint EU military operati…