refactor(crypto): move base58 functions to utils

[faustbrian]

Move the base58 specific code out of the address identity because identities shouldn't expose anything besides methods to generate/validate the type of identity it is.

What kind of change does this PR introduce?

• Bugfix
• Feature
• Refactor
• Performance
• Tests
• Build
• Documentation
• Code style update
• Continuous Integration
• Other, please describe:

Does this PR introduce a breaking change?

• Yes
• No

Does this PR release a new version?

• Yes
• No

If yes, please describe the impact and migration path for existing applications:

The PR fulfills these requirements:

• It's submitted to the develop branch, not the master branch
• All tests are passing
• New/updated tests are included

If adding a new feature, the PR's description includes:

• A convincing reason for adding this feature (to avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it)

[codecov-io]

Codecov Report

Merging #2675 into 2.6 will decrease coverage by 0.01%.
The diff coverage is 84.84%.

@@            Coverage Diff             @@
##              2.6    #2675      +/-   ##
==========================================
- Coverage   64.88%   64.86%   -0.02%     
==========================================
  Files         362      363       +1     
  Lines        8201     8203       +2     
  Branches      418      382      -36     
==========================================
  Hits         5321     5321              
- Misses       2841     2847       +6     
+ Partials       39       35       -4

Impacted Files	Coverage Δ
packages/crypto/src/identities/address.ts	100% <100%> (ø)	⬆️
packages/crypto/src/transactions/types/transfer.ts	100% <100%> (ø)	⬆️
packages/crypto/src/transactions/serializer.ts	89.25% <100%> (+0.08%)	⬆️
packages/crypto/src/utils/base58.ts	100% <100%> (ø)
packages/crypto/src/crypto/bip38.ts	96.49% <100%> (-0.86%)	⬇️
...crypto/src/transactions/types/timelock-transfer.ts	40% <33.33%> (-2.86%)	⬇️
packages/core-transactions/src/utils.ts	66.66% <50%> (ø)	⬆️
...ges/crypto/src/transactions/types/multi-payment.ts	38.09% <50%> (-2.82%)	⬇️
packages/core-api/src/formats.ts	44.44% <50%> (ø)	⬆️
packages/crypto/src/errors.ts	81.63% <0%> (-2.05%)	⬇️
... and 5 more

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