doc for rchash is wrong

[jpritikin]

Context

1.18

Summary

rchash requires the random string to be repeated. This doesn't match the documentation.

Expected behavior

See https://docs.ethswarm.org/docs/bee/working-with-bee/staking/#check-node-performance

Actual behavior

curl http://glow.lan:1635/rchash/10/123456/123456

Possible solution

Fix bee or fix documentation

[jpritikin]

Also, bee returns "duration": 4842253994526 in unknown units (nanoseconds?) instead of "Time": "2m54.087909745s" as documented.

[rampall]

Also, bee returns "duration": 4842253994526 in unknown units (nanoseconds?) instead of "Time": "2m54.087909745s" as documented.

related - https://github.com/ethersphere/bee-docs/issues/530