git-secret changes should have -q quiet mode that sets exit code nonzero if changes exist

[aberezin]

Consider adding a -q --quiet flag to git-secret-changes which would output nothing to stdout but set the exit code to 1 if there are any changes and 0 otherwise

This would match the git-diff --quiet flag (which forces exit codes matching the diff program).

[sobolevn]

Great idea! We will include this into 0.5.0

[joshrabinowitz]

Moved from 0.5.0 to 0.6.0