Set the times for constant calibrations to prevent pointless error messages
These changes modify the reference calibration times for the constant calibration files. These files are used by the SenseMonitor program and are an obsolete remnant from when SenseMonitor did frequency-domain calibration of the differential arm signal. This calibration was performed by calculating a frequency-dependent inverse response function R(f) = (1 + a(t)b(t)G(f)) / (a(t)C(f)), where G(f) and C(f) are the open loop gain and the sensing function and a(t) and b(t) are the time dependent gains. Because the SenseMonitor input channels are now h(t) or a weighted h(t), the reference calibration functions become constants, but the calibration stage still needs to know these functions (this is not true for sensemonitor2). Since there is no time dependence the a(t), b(t) are both 1.0 at all times, but the reference calibration function needs to know this versus time. The a(t) and b(t) tables in the reference calibration file recently expired resulting in SenseMonitor producing an error message for each measured point. This MR changes the time-dependent tables in the Reference Calibration xml files to cover times from GPS 1330000000 - 1530000000 (through Feb 2028). Presumably by that time, either sensemonitor2 or some other monitor that does not require the frequency-dependent calibration will be in use.