Re: [PATCH] test-lib: fix non-portable pattern bracket expressions

SZEDER Gábor [off-list ref] writes:

Use a '!' character to start a non-matching pattern bracket
expression, as specified by POSIX in Shell Command Language section
2.13.1 Patterns Matching a Single Character [1].

I used '^' instead in three places in the previous three commits, to

Ah, thanks for catching them.  We should have caught these during
review.

Should go on top of 'sg/stress-test'.

Thanks.