Incorrect flow term label written to MAW binary budget file.

[RichardWinston]

Describe the bug
In table 40 of mf6io.pdf, it says that the last term written to the MVR budget file is FW-RATE-TO-MVR
but the actual label written for this term is CONSTANT-TO-MVR.

[emorway-usgs]

test_gwf_maw11.txt.txt
I started looking into this by creating a new test problem (attached); it seems there's a bit more going on than first anticipated. Will chat with the lead developers to try and figure out what's needed.

I think the table will also need to be amended with something to the effect:
CONSTANT-TO-MVR 6 1/nmawwells Calculated flow from a multi-aquifer well with STATUS set to CONSTANT to the MVR Package. Only saved if MVR Package is used in the MAW Package. The multi-aquifer well number is written to (ID1) and (ID2).