Werk #15541: Replace BGP peer check plugin

The Arista BGP check plugin is replaced by a more general BGP peer check plugin.

The following new features are added:

• Introduction of new SNMP sections cisco_bgp_peerv2 and cisco_bgp_peerv3
• Add description or VrfName if available which is available as check result and service label
• Add established time which is available as check result aswell as a metric
• Move less important check output to details
• Add configurable state mapping for admin state and peer state

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