Balance integration fix

[faculerena]

Summary

• [N] y/n | Does it introduce breaking changes?
• [N] y/n | Is it dependant on the specific version of cargo-contract or pallet-contracts?

Updated the default balance in integration tests.

Description

We updated the default balance in integration tests to be the same as in e2e-tests. This is not definitive, as we want opinions if this should be like this.

Checklist before requesting a review

• [X] My code follows the style guidelines of this project
• [ ] I have added an entry to CHANGELOG.md
• [X] I have commented my code, particularly in hard-to-understand areas
• [ ] I have added tests that prove my fix is effective or that my feature works
• [X] Any dependent changes have been merged and published in downstream modules

[faculerena]

I changed the value to be the same as the testnet genesis. This is the same value that this test gives in an e2e test.

  let alice_balance = client
      .balance(ink_e2e::account_id(ink_e2e::AccountKeyring::Alice))
      .await
      .expect("Failed to get account balance");

In this case, alice_balance is (1 << 60), and for each account in the keyring this is true too, except for one and two, that is 0.