Token fields are not updated when token's implementation updates

[Romsters]

🐛 Bug Report

If token contract is a Proxy, when implementation changes the token's fields in the explorer DB are not updated. Each time when implementation is updated token name, decimals and symbol have to be updated.

More info here:

zkSync-Community-Hub/zksync-developers#245

🔄 Reproduction Steps

• Create a proxy token contract;
• Make a transfer;
• Change implementation and update decimals value;
• Make another transfer;
• Both transfers would have the original decimals value;

🤔 Expected Behavior

After every implementation update token's name, symbol and decimals should be updated.

😯 Current Behavior

On implementation update token's name, symbol and decimals are not updated.