docs: fix mersenne rand min max confusion

[gregoriomario]

although mersenne automatically swap the value if min is bigger than max, but it's a good practice to clear out the confusion.

Fix #775

[codecov]

Codecov Report

Merging #839 (d6d3465) into main (2a6003f) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #839   +/-   ##
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  Coverage   99.67%   99.67%           
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  Files        2110     2110           
  Lines      225732   225732           
  Branches      979      979           
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  Hits       224992   224992           
  Misses        720      720           
  Partials       20       20           

Impacted Files	Coverage Δ
src/modules/mersenne/index.ts	100.00% <100.00%> (ø)

[Shinigami92]

I assume it was implemented with max as first param, so that a user can use it with faker.mersenne.rand(6) so without a min argument and it just has a default min = 0