fix: add approval for subnet join

[cryptoAtwill]

Adding owner approve for subnet register. This means a subnet can be registered in the gateway only if the owner approves it.

[karlem]

Looks good. Just small details.

[karlem]

@cryptoAtwill I have approved but I think you need to update the e2e tests. Given the error message below it seems related to your fix.

OUT: 2025-05-20T09:27:13.660005Z ERROR ipc_provider::manager::evm::error_parsing: contract reverted with error: NotAuthorized
OUT: 2025-05-20T09:27:13.660958Z ERROR ipc_cli: main process failed: error processing command Some(Subnet(SubnetCommandsArgs { command: Join(JoinSubnetArgs { from: Some("0x9a2954b87d8745df0b1010291c51d68ae9269d43"), subnet: "/r1126193293194756/f410fhwibtof7hp6v5f453q5soyn6ksxym7chbqata2q", collateral: 1e-9, initial_balance: Some(30.0) }) })): Contract call reverted with data: 0x4a0bfec10000000000000000000000003d9019b8bf3bfd5e979ddc3b2761be54af867c47   

[cryptoAtwill]

@karlem Yeah, I looked into it, I realized this is almost impossible to fix. Check out this issue: #1348. With the above issue, it means we cannot approve any subnet to be registered.

[phutchins]

Aiming to merge tomorrow.

[drahnr]

Do we need a deployment documentation update when merging this?