Refactor `pallet-state-trie-migration` to `fungible::*` traits (#1801)

## Summary

This PR consolidates `pallet-state-trie-migration` as a part of
https://github.com/paritytech/polkadot-sdk/issues/226 /
https://github.com/paritytech/polkadot-sdk/issues/171:

`pallet-state-trie-migration`:
- [x] replace `Currency` with `fungible` traits
- [x] run benchmarks
- [x] refactor to `DefaultConfig`

`pallet_nicks`:
- [x]  remove

others:
- [x] remove `as Fn*` or `asFun*` stuff based on discussion
[here](https://github.com/paritytech/polkadot-sdk/issues/226#issuecomment-1822861445)

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Co-authored-by: Richard Melkonian <35300528+0xmovses@users.noreply.github.com>
Co-authored-by: command-bot <>