Dynamic input for popover

[zkrami]

Issue type

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• bug report
• feature request

Issue description

Current behavior:
When I bind a value to popover the content of the popover doesn't change whenever I change the binded value

Expected behavior:
the popover content should change if the binding value changed

Steps to reproduce:
create a template use [nbPopover] directive and bind it to value.
the content of the popover won't change unless it's recreated .