[CP-SAT] remove gap message when gap is 0
[CP-SAT] remove gap message when gap is 0

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