AppVeyor: build for "all" language instead.
AppVeyor: build for "all" language instead.

Since we only have one job we can't have a specific job per language
(otherwise it take severals hours)
To revert if we buy more workers...

google/or-tools,or-tools/or-tools,or-tools/or-tools,or-tools/or-tools,or-tools/or-tools,google/or-tools,google/or-tools,google/or-tools,or-tools/or-tools,google/or-tools,google/or-tools,or-tools/or-tools