tests 258 and 338 fail on macOS

[scharlton2]

$ ctest -C Release -I 1,1,1,258,338
Test project /Users/charlton/source/repos/coupled/phreeqc3/_build
    Start   1: ex1
1/3 Test   #1: ex1 ..............................   Passed    0.04 sec
    Start 258: mytest.P_Vm
2/3 Test #258: mytest.P_Vm ......................***Failed    0.23 sec
    Start 338: mytest.rho_H3PO4
3/3 Test #338: mytest.rho_H3PO4 .................***Failed    0.04 sec

33% tests passed, 2 tests failed out of 3

Total Test time (real) =   0.34 sec

The following tests FAILED:
	258 - mytest.P_Vm (Failed)
	338 - mytest.rho_H3PO4 (Failed)
Errors while running CTest
Output from these tests are in: /Users/charlton/source/repos/coupled/phreeqc3/_build/Testing/Temporary/LastTest.log
Use "--rerun-failed --output-on-failure" to re-run the failed cases verbosely.

Files

P_Vm.zip

rho_H3PO4.zip