fix: refactored precompile contracts and tests folders

[quiet-node]

Description: This PR refactorred the contracts and tests folders in a way that would group all precompile related SCs into one dedicated folder, precompile.

The folders that have been refactored and renamed are:

• hts-precompile --> hedera-token-service
• exchange-rate-precompile --> exchange-rate
• native-precompile --> native
• util-precompile --> pseudo-random-number-generator
• safe-hts is now moved inside hedera-token-service

New folder, hedera-account-service, is added to precompile folder to hold HederaAccountService precompile contract and IHRC632 interface.

The test folder is also modified to match up with the modified structure in the contracts folder.

Related issue(s):

Fixes #810

Notes for reviewer:

Checklist

• [ ] Documented (Code comments, README, etc.)
• [ ] Tested (unit, integration, etc.)

[github-actions[bot]]

Test Results

  16 files  +  1    77 suites  +3   7m 25s :stopwatch: +27s 254 tests +10  247 :heavy_check_mark: +11  7 :zzz: ±0  0 :x:  - 1  263 runs  +10  255 :heavy_check_mark: +11  8 :zzz: ±0  0 :x:  - 1 

Results for commit b1343030. ± Comparison against base commit 4241394e.

:recycle: This comment has been updated with latest results.