find: add -daystart argument in example

[dwdh]

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Option is wrong. want to display files older than 7 days, should use the -daystart -mtime -7 or -ctime -6.
for example:

$ find . -daystart -mtime -7
.
./test_2021-09-04.log
./test_2021-09-07.log
./test_2021-09-05.log
./test_2021-09-08.log
./test_2021-09-03.log
./test_2021-09-06.log
./test_2021-09-09.log

$ find . -ctime -6
.
./test_2021-09-04.log
./test_2021-09-07.log
./test_2021-09-05.log
./test_2021-09-08.log
./test_2021-09-03.log
./test_2021-09-06.log
./test_2021-09-09.log

[CLAassistant]

All committers have signed the CLA.

[mfrw]

LGTM .. thank you for the contribution.
TIL -> -daystart

[sbrl]

Great catch - thanks, @dwdh!