disable testing for --core=light if srun lacks the spank plugin to support it

testsuite/expect/test1.39

@@ -38,6 +38,32 @@ set file_prog   "test$test_id.prog"
 
 print_header $test_id
 
+#
+# Test if SPANK plugin for core files is installed
+#
+set core_enabled 0
+log_user 0
+set srun_pid [spawn $srun --help]
+expect {
+	-re "--core=format" {
+		set core_enabled 1
+		exp_continue
+	}
+	timeout {
+		send_user "\nFAILURE: srun not responding\n"
+		slow_kill $srun_pid
+		exit 1
+	}
+	eof {
+		wait
+	}
+}
+log_user 1
+if {$core_enabled == 0} {
+	send_user "\nWARNING: core file optioins not supported\n"
+	exit 0
+}
+
 #
 # Test if "light" core file supported
 #