Release v1.6.0: support for Bridge Hub Polkadot 1_002_002

Docker reference: paritytech/substrate-relay:v1.6.0

Rococo: 1_010_000;
Westend: 1_010_000;
Kusama: 1_001_002;
Polkadot: 1_001_002;
Rococo Bridge Hub: 1_010_000;
Westend Bridge Hub: 1_010_000;
Kusama Bridge Hub: 1_002_000;
Polkadot Bridge Hub: 1_002_002;
Rococo Bulletin: not supported yet;
Polkadot Bulletin: not supported yet.

What's Changed

• Fix deploy step by @BulatSaif in #2992
• Fixed relayer metric value by @svyatonik in #2993
• Relay v1.6.0: added support for BHP 1_002_002 by @svyatonik in #2999

Full Changelog: v1.5.1...v1.6.0