How can I manipulate asset prices in a test/forked environment to test out a liquidation contract?

These are the steps to update an asset oracle:

1. Deploy a mock oracle with the new price passed by constructor
2. Call to AaveOracle contract to the method setAssetSources with the underlying asset address and the new MockAggregator contract address;

*1. Mock aggregator code;
*2. Method setAssetSouces at Aave Oracle;