Handle port state in fwdport implementations

[DanG100]

• simplified port state proto
• use forwarding notification instead of netlink for link state in interface reconciler
• kernel and tap port implementation handle the state correctly

[github-actions]

Pull Request Test Coverage Report for Build 5026585253

• 5 of 152 (3.29%) changed or added relevant lines in 8 files are covered.
• 2 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.001%) to 2.346%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
dataplane/internal/engine/engine.go	0	3	0.0%
dataplane/internal/kernel/kernel.go	0	3	0.0%
dataplane/forwarding/fwdport/ports/group.go	1	6	16.67%
dataplane/forwarding/fwdport/ports/kernel.go	0	9	0.0%
dataplane/handlers/interface.go	0	45	0.0%
dataplane/forwarding/fwdport/ports/tap.go	0	82	0.0%

Files with Coverage Reduction	New Missed Lines	%
dataplane/forwarding/fwdport/ports/kernel.go	1	7.92%
dataplane/forwarding/fwdport/ports/tap.go	1	1.81%

Totals
Change from base Build 5018244714:	-0.001%
Covered Lines:	12382
Relevant Lines:	527858

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💛 - Coveralls