bash: disable timeout to prevent Expect from exiting early

The default timeout is only 10 seconds, where the bash tests won't
complete on most systems.  Then expect will exit early, with bash tests
running in background.  We won't like this.

chapter08/bash.xml

@@ -80,7 +80,9 @@
     class="username">tester</systemitem> user:</para>
 
 <screen><userinput remap="test">su -s /usr/bin/expect tester &lt;&lt; EOF
-spawn make tests; expect eof;
+set timeout -1
+spawn make tests
+expect eof
 EOF</userinput></screen>
 
     <para>Install the package:</para>