hash.go hash error covered and linter error fixed

[yusufpapurcu]

Error covered without change function definition

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[yusufpapurcu]

@googlebot I signed it!

[pborman]

These error checks are unnecessary:

type Hash interface {
    // Write (via the embedded io.Writer interface) adds more data to the running hash.
    // It never returns an error.
    io.Writer

[yusufpapurcu]

So we need to add //nolint:errcheck because if we don't add it will fails in linting.

[pborman]

Thank you. FYI, the other option is just saying _, _ = h.Write(...)