fix(due-date): automatically open native date picker when choosing a due date

[theoholl]

Fixes #8110

Summary

When clicking "Choose a date" in the due date menu, the card's due date was set to next day 8am but the native date/time picker did not open, requiring an extra click on the date field to actually change the value.

Changes

• DueDateSelector.vue: after initializing the due date via "Choose a date", automatically open the native datetime-local picker (showPicker(), falling back to .focus()) once the value has been persisted and rendered.

[github-actions]

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