remove ADMCoupling from test cases, use ML_ADMConstraints instead of (nonexistent) ADMConstraints

GRHydro: remove ADMCoupling from tests

GRHydro_InitData: remove ADMCoupling from tests

GRHydro: remove ADMCoupling from tests

GRHydro: use ML_ADMConstraints in tests

GRHydro: regenerate constraint data for tests that used ADMConstraints

ADMConstraints and ML_ADMConstraints differ in detail:

• ML_ADMConstraints is always 4th order accurate FD, ADMConstraints depends on ADMMacros's order

• ML_ADMConstraints uses a "flat" boundary condition with boundary width width, ADMConstraints uses "static" (zero in practise) and 1 point wide (at least in this set of tests)

I have verified that the test using ML_ADMConstraints pass with the old ADMConstraints data if one modifies ML_ADMConstraints to

• use 2nd order finite differencing

• pretends the boundary is 1 point wide