checkkey.sh: Fix bogus character in case statement

[mat]

The change is wrong, the code is correct. See sh(1):

The pattern can actually be one or more patterns (see Shell Patterns described later), separated by ‘|’ characters. Tilde expansion, parameter expansion, command substitution, arithmetic expansion and quote removal are applied to the word. Then, each pattern is expanded in turn using tilde expansion, parameter expansion, command substitution and arithmetic expansion and the expanded form of the word is checked against it. If a match is found, the corresponding list is executed. If the selected list is terminated by the control operator ‘;&’ instead of ‘;;’, execution continues with the next list, continuing until a list terminated with ‘;;’ or the end of the case command.

[jlduran]

I guess that's what I get for using macOS. You are absolutely right. Sorry for the noise.

[jlduran]

It has been addressed by D46453.