NI bench: power on the power meter was too low

This afternoon the opertator (see Operation report - Afternoon shift) reported a warning from ALP: the NI laser possibly being off due to low signal on TCS_power_DC.

After a quick investigation, I saw that the power on the power meter
was very low because of the setting of the wave-plate angle. So I
simply rotated the plate to shine more power on the power meter: the
flag on the DMS is green again.