Add support for Soroban external calls 🎉 #7053

Job	Run time
Docs	1m 15s
Linux x86-64	35m 39s
Container Image	12m 0s
Linux Arm	19m 28s
Mac Intel	1s
Repolinter	26s
Stdlib	6s
Windows	8m 54s
Mac Arm	7m 36s
Mac Universal Binary	0s
Polkadot Integration test with subxt	0s
Anchor Integration test	0s
Solana Integration test	0s
Polkadot Integration test	0s
Visual Code Extension	0s
Soroban Integration test	0s
Coverage report	0s
	1h 25m 25s

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