Makefile: fix clab bgp cleanup

[zhangzujian]

Pull Request

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What type of this PR

Examples of user facing changes:

• Features
• Bug fixes
• Docs
• Tests

Which issue(s) this PR fixes

Fixes #(issue-number)

WHAT

🤖[deprecated] Generated by Copilot at ce35fa3

Improved the Makefile to support BGP testing with container lab. Fixed volume mount paths and added make targets for clab-bgp and clab-bgp-ha scenarios.

🤖[deprecated] Generated by Copilot at ce35fa3

Sing, O Muse, of the skillful coder who changed the paths
Of the volume mounts for clab-bgp and clab-bgp-ha, files of power
To avoid the strife of conflicts and match the commands of clab
The tool of many wonders, that creates and destroys container labs

HOW

🤖[deprecated] Generated by Copilot at ce35fa3

• Change volume mount paths and commands for clab-bgp.yaml and clab-bgp-ha.yaml files to avoid conflicts with other clab files (link, link, link, link)
• Add support for BGP peering with external routers in a container lab environment using clab-bgp.yaml and clab-bgp-ha.yaml files (link, link)
• Add a make target to clean up the container lab environment for BGP peering with external routers using clab destroy command (link, link)