Remove unused import

Author: timfel

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/cext/common/CExtContext.java

@@ -59,7 +59,6 @@
 import org.graalvm.shadowed.com.ibm.icu.impl.Punycode;
 import org.graalvm.shadowed.com.ibm.icu.text.StringPrepParseException;
 
-import com.oracle.graal.python.builtins.PythonOS;
 import com.oracle.graal.python.builtins.objects.cext.capi.CApiContext;
 import com.oracle.graal.python.builtins.objects.cext.common.CExtCommonNodes.CheckFunctionResultNode;
 import com.oracle.graal.python.builtins.objects.cext.common.LoadCExtException.ApiInitException;