refactor(ledger): Extend class IcrcLedgerCanister with common IcrcCanister

[AntonioVentilii]

Motivation

Class IcrcLedgerCanister can actually extend abstract IcrcCanister (see PR #1285).

And in fact, the method to fetch the balance is the exact same that is already developed in IcrcCanister.

Changes

• Change the class extension of IcrcLedgerCanister from Canister to IcrcCanister.
• Remove redundant balance method.

Tests

No more tests needed, since the method balance is already tested for IcrcCanister.

[github-actions]

size-limit report 📦

Path	Size
@dfinity/ckbtc	8.2 KB (0%)
@dfinity/cketh	3.69 KB (0%)
@dfinity/cmc	1.59 KB (0%)
@dfinity/ledger-icrc	5.12 KB (-0.4% 🔽)
@dfinity/ledger-icp	7.16 KB (0%)
@dfinity/nns	27.45 KB (0%)
@dfinity/nns-proto	141 KB (0%)
@dfinity/sns	16.43 KB (0%)
@dfinity/utils	5.11 KB (0%)
@dfinity/zod-schemas	627 B (0%)
@dfinity/ic-management	4.47 KB (0%)
@icp-sdk/canisters/ckbtc	8.2 KB (0%)
@icp-sdk/canisters/cketh	3.69 KB (0%)
@icp-sdk/canisters/cmc	1.59 KB (0%)
@icp-sdk/canisters/ledger/icrc	5.12 KB (-0.4% 🔽)
@icp-sdk/canisters/ledger/icp	7.16 KB (0%)
@icp-sdk/canisters/nns	27.45 KB (0%)
@icp-sdk/canisters/sns	16.43 KB (0%)
@icp-sdk/canisters/ic-management	4.47 KB (0%)

[peterpeterparker]

LGTM, thx