nc_test_run_pnetcdf_test fails in 4.9.0

[ArchangeGabriel]

63/258 Testing: nc_test_run_pnetcdf_test
63/258 Test: nc_test_run_pnetcdf_test
Command: "/usr/bin/bash" "-c" "export srcdir=/build/netcdf-openmpi/src/netcdf-c-4.9.0/nc_test;export TOPSRCDIR=/build/netcdf-openmpi/src/netcdf-c-4.9.0;/build/netcdf-openmpi/src/build/nc_test/run_pnetcdf_test.sh run_pnetcdf_test.sh "
Directory: /build/netcdf-openmpi/src/build/nc_test
"nc_test_run_pnetcdf_test" start time: Jun 27 14:13 UTC
Output:
----------------------------------------------------------
/usr/bin/bash: line 1: /build/netcdf-openmpi/src/build/nc_test/run_pnetcdf_test.sh: No such file or directory
<end of output>
Test time =   0.00 sec
----------------------------------------------------------
Test Failed.
"nc_test_run_pnetcdf_test" end time: Jun 27 14:13 UTC
"nc_test_run_pnetcdf_test" time elapsed: 00:00:00
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The file was changed for autotools in #2284, but not CMake.

[WardF]

Adding a fix for this now, both in our code and in our testing.