fix: minPrecision overiding valid digits inside precision range

[LuizAsFight]

fix bug that would make this test fail:

    expect(
      bn('100100020000').format({
        minPrecision: 4,
        precision: 8,
      })
    ).toEqual('100.10002');

Closes #572

[github-actions]

Coverage report

St.❔	Category	Percentage	Covered / Total
🟢	Statements	90.2%	3597/3988
🟡	Branches	72.77%	700/962
🟢	Functions	87.82%	721/821
🟢	Lines	90.21%	3447/3821

Test suite run success

543 tests passing in 49 suites.

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