docs: Fullnode Typings [6] - Signatures

[tuliomir]

Acceptance Criteria

• Adds typings to the Signatures methods

Security Checklist

• Make sure you do not include new dependencies in the project unless strictly necessary and do not include dev-dependencies as production ones. More dependencies increase the possibility of one of them being hijacked and affecting us.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.79%. Comparing base (1a929ba) to head (d5c0235).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #988      +/-   ##
==========================================
- Coverage   86.81%   86.79%   -0.02%     
==========================================
  Files         113      113              
  Lines        8507     8507              
  Branches     1884     1876       -8     
==========================================
- Hits         7385     7384       -1     
- Misses       1094     1095       +1     
  Partials       28       28              

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[raul-oliveira]

Looks good. IMO we can have a type to simplify