In the old days it was not a good idea to do a resistance check of an MC cartridge because the meter would put a substantial DC current supplied by a battery through the coils which might leave a magnetic field.
Then in the new days the DVMs put an AC signal through the circuit under test instead. The concern is really not a lot different- an AC current through the coils could demagnetize the cartridge somehow. In practice I've not seen it happen, but if you are concerned I would get a 50-ohm resistor and put that in series with the cartridge when doing the test, then subtract the actual resistance of the resistor from the reading.
Then in the new days the DVMs put an AC signal through the circuit under test instead. The concern is really not a lot different- an AC current through the coils could demagnetize the cartridge somehow. In practice I've not seen it happen, but if you are concerned I would get a 50-ohm resistor and put that in series with the cartridge when doing the test, then subtract the actual resistance of the resistor from the reading.