Decide CBC template cutoff frequencies

Per !126 (closed), we should decide what the CBC template's inclusive min frequency should be. Previously, it was found using the startFrequencyHz function, but now, it is locked to the user's inputted value: https://git.ligo.org/howard.deshong/bayeswave-cpp/-/blob/03dbf5b2ada6f0e81c117cd3d19404ad84e47567/src/model_elements/bases/cbc/cbc_geocenter_waveform.cpp#L238-245 and https://git.ligo.org/howard.deshong/bayeswave-cpp/-/blob/03dbf5b2ada6f0e81c117cd3d19404ad84e47567/src/model_elements/bases/cbc/cbc_geocenter_waveform.cpp#L439-446