fix(collections): make use of exported iterator from dbm

[mmsqe]

Description

Closes: #24464, depends on cosmos/cosmos-db#127

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[ironbird-prod]

Ironbird - launch a network

To use Ironbird, you can use the following commands:

• /ironbird start OR /ironbird start --load-test-config= - Launch a testnet with the specified chain and load test configuration.
• /ironbird chains - List of chain images that ironbird can use to spin-up testnet
• /ironbird loadtests - List of load test modes that ironbird can run against testnet

Custom Load Test Configuration

You can provide a custom load test configuration using the `--load-test-config=` flag:

/ironbird start cosmos --load-test-config={
  "block_gas_limit_target": 0.75,
  "num_of_blocks": 50,
  "msgs": [
    {"weight": 0.3, "type": "MsgSend"},
    {"weight": 0.3, "type": "MsgMultiSend"},
	{"weight": 0.4, "type": "MsgArr", "ContainedType": "MsgSend", "NumMsgs": 3300}
  ]
}

Use /ironbird loadtests to see more examples.