fix invalid command in build instructions

[fatso83]

I tried the supplied command, it failed, I checked the help docs and found config, tried that and I could see that my config file now was changed. so it seems the old instructions are wrong.

[CLAassistant]

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[eliericha]

Hello @fatso83 ,

Thank you for the contribution. However alr config is a deprecated Alire command and alr settings is the replacement. So the current build instructions are up to date.

This change occurred in Alire 2.0 (search for alr config in the Alire changelog) which is the documented version for building. Perhaps you were using an older Alire version?

[fatso83]

indeed. sorry for that. got alire from the current ubuntu repos. now getting from the relases on github.