docs: improve examples of `stats/base/dists/gumbel`#2140

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olenkabilonizhka:olenkabilonizhka-fix/Improve-README-examples-of-stats/base/dists/gumbelolenkabilonizhka/stdlib:olenkabilonizhka-fix/Improve-README-examples-of-stats/base/dists/gumbelCopy head branch name to clipboard