update to MOM6 main 20240729 commit (gfdl-to-main-2024-05-31)

[jiandewang]

MOM6 main repo. merged the "gfdl-to-main-2024-05-31" on 20240729 (see detail at mom-ocean/MOM6#1631). Need to pull it into dev/emc correspondingly.
Note this PR will require a new BL because

• a new variable "h_ML" is being added in the restart file (see detail at mom-ocean/MOM6@7305528)

• a bug fixing on "incorrect PPM:H3 tracer advection stencil" (see detail at NOAA-EMC/MOM6@3fac1c5). Note we can retain original answer by setting USE_HUYNH_STENCIL_BUG=True but here we are going to use its default value (False) since this is a real bug fixing.

we will also set DEFAULT_ANSWER_DATE=20231231 in 5x5 setting as currently it is using its default value which is too aggressive (suggested by GFDL)