Add resource_manager_tags to VPN resources

[NandiniAgrawal15]

Added resource_manager_tags support to HaVpnGateway, VpnTunnel, ExternalVpnGateway, and VpnGateway (Classic). Included handwritten acceptance tests.

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PR created automatically by Jules for task 16027173592371154567 started by @NandiniAgrawal15

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