feat(bitmex-client): introduce getter for instrument from bitmex #6376

Job	Run time
10101 node tests	8m 41s
lint-commits	8s
generate-ffi	5m 4s
formatting-dprint	20s
Format and lint Flutter code	50s
clippy	6m 18s
payout-curve	6m 19s
e2e_tests_prepare	10m 0s
unit-tests	11m 12s
e2e-tests (./target/debug/deps/e2e_basic-dc16b05106682ee8)	5m 9s
e2e-tests (./target/debug/deps/e2e_close_position-e9b6d91a1c45a695)	6m 10s
e2e-tests (./target/debug/deps/e2e_collaborative_close_channel-66f5271d7bca8d36)	5m 46s
e2e-tests (./target/debug/deps/e2e_collaborative_revert-57d82af17457a983)	5m 31s
e2e-tests (./target/debug/deps/e2e_force_close_position-ae7bba98a32685ae)	5m 28s
e2e-tests (./target/debug/deps/e2e_force_close_settled_channel-1cc45683b6bd5d25)	6m 1s
e2e-tests (./target/debug/deps/e2e_open_position-63656d864d830c98)	5m 19s
e2e-tests (./target/debug/deps/e2e_open_position_small_utxos-135ea868e65ac8d7)	5m 28s
e2e-tests (./target/debug/deps/e2e_open_position_with_external_funding-fe2e505cf4dbab4d)	4m 53s
e2e-tests (./target/debug/deps/e2e_reject_offer-234657b445858367)	5m 34s
e2e-tests (./target/debug/deps/e2e_resize_position-49ac88ffc5bb1ac5)	5m 55s
e2e-tests (./target/debug/deps/e2e_restore_from_backup-18d4104a50362245)	5m 32s
e2e-tests (./target/debug/deps/e2e_rollover_position-f6b7a150b66ecf5a)	5m 44s
e2e_tests_check	1s
	2h 1m 23s

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