BMI_testcase_m01_BuffaloRiver_TN_USA.mat has been changed

[SarahAlidoost]

(cc @Peter9192) Our MarrmotM01 notebook works with BMI_testcase_m01_BuffaloRiver_TN_USA.mat. However, this file is changed and the parameter delta_t_days is changed to delta_t. Note that we also set this parameter in esmvtool diagnostics. Perhaps, we need to keep the old copy of data in ewatercycle repo.

[Peter9192]

Note that thanks to version control, the old version is still accessible, at this link: https://github.com/wknoben/MARRMoT/blob/92714093fdabd5e99957612cb3dd96b5c445e706/BMI/Config/BMI_testcase_m01_BuffaloRiver_TN_USA.mat