Adding maximumFee param

[vlasfama]

Description

• Adding maximumFee param.
• Increased change unit from 10^8 to 10^9

Related issue(s)

closing #360

Checklist

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• My code follows the code style of this project.
• I have added tests to cover my changes.
• All new and existing tests passed.
• CHANGELOG is updated.

[codecov]

Codecov Report

Merging #399 (8a27bbe) into main (5d75645) will decrease coverage by 0.06%.
The diff coverage is 71.11%.

@@            Coverage Diff             @@
##             main     #399      +/-   ##
==========================================
- Coverage   80.43%   80.36%   -0.07%     
==========================================
  Files         147      147              
  Lines        6751     6759       +8     
==========================================
+ Hits         5430     5432       +2     
- Misses       1052     1058       +6     
  Partials      269      269