fix: query tx events with >= and <= operators

[rootulp]

Part of celestiaorg/celestia-app#2098

Testing

Before

$ curl http://localhost:1317/cosmos/tx/v1beta1/txs?events=tx.height%3C=10
{
"code": 3,
"message": "invalid event; event tx.height\u003c=10 should be of the format: {eventType}.{eventAttribute}={value}",
"details": [
]
}%

After

$ curl http://localhost:1317/cosmos/tx/v1beta1/txs?events=tx.height%3C=10
{
  "txs": [
  ],
  "tx_responses": [
  ],
  "pagination": null,
  "total": "0"
}%

FLUPs

1. Cut a release of this repo and bump in celestia-app
2. Get a fix for this issue merged to upstream cosmos-sdk fix: query tx events with >= and <= operators cosmos/cosmos-sdk#16994 and pull it here