Fixed inconsistency in PlotTestHarness

Also removed hack that was introduced in 9676223

tests/run_tests.py

@@ -509,7 +509,4 @@ for test in tests:
         print(' '*len(test)+tests[test].msg)
         return_code = 1
 
-with open(logfilename) as fh:
-    print(fh.read())
-
 sys.exit(return_code)

tests/test_plot_basis/results_true.dat

@@ -1 +1 @@
-8953968071de7c660f8ce07a28b11bb7c37d7150dd2bfd800483e0f76e021d279b100560faf1fb0cd9b8398a1f86b6166ea21f331f265fcf8662b35e70359cad
+6a2400a95ea5baee432dd04a85252818d682004dc80b225b99c4bbc7cfd20d8523bd8e5df8a272df288cb2f300e5eee55f7ffa7b4d28ea64f92b78839ab0e86b

tests/test_plot_mask/results_true.dat

@@ -1 +1 @@
-a32df9c5ab026c40d1b81e303da38cad9a1a6263165087539520d892d0a9cb40193f94f2f5f4d9c94e7e9208121847099bf0c47694d3fc1d01c9e4f57555208b
+d888a734d6e69c5ca92457dc865c4defd8a1d8a1d4a01e0c8e7c528dde25d96df1283da37889dac0857329051958be2f2b491f2fd2bc22c8424a60ec6cda04bd

tests/testing_harness.py

@@ -186,7 +186,7 @@ class PlotTestHarness(TestHarness):
 
         # Read the plot files.
         outstr = bytes()
-        for fname in plot_files:
+        for fname in sorted(plot_files):
             with open(fname, 'rb') as fh:
                 outstr += fh.read()