Expand `wp s3-uploads verify` command to check all required permissions

[chrisvanpatten]

Right now, the wp s3-uploads verify CLI command is able to verify write and delete, but does not seem to internally call any functions which would also check the ListObjects permissions.

For context, we had an instance where our IAM permissions were mis-configured so we couldn't list objects, but writes/deletes were totally fine. wp s3-uploads verify didn't catch the issue (although wp s3-uploads ls did return the errors, which is how we ended up catching it).