absinterp failures started with gcc 7 onwards, rather than gcc 8

Author: davidmalcolm

run-test-suite.py

@@ -776,7 +776,7 @@ def exclude_tests_below(path):
     exclude_test('tests/cpychecker/PyArg_ParseTuple/without_PY_SSIZE_T_CLEAN')
 
 # absinterp and thus the refcount-checker have bit-rotted:
-if GCC_VERSION >= 8000:
+if GCC_VERSION >= 7000:
     exclude_tests_below('tests/cpychecker/absinterp')
     exclude_tests_below('tests/cpychecker/refcounts')