logilab-devtools #72434 fix sources.list corruption when using lgp shell [resolved]

We must not use the OTHERMIRROR env variable due to conflictual combinaison with the command line parameter "--othermirror" used in shell command.

lgp shell will systematically override the static mirror list managed by lgp from /etc/lgp/sources.list.*

prioritynormal
typebug
done in0.18.3
load0.500
load left0.000
closed by#1a064c88dda2 lgp: fix sources.list corruption when using lgp shell (closes: #72434)