changed kafka version from 6.10 to 6.11

Signed-off-by: jamesbw <github+jamesbw@squareup.com>
excluded signatures in examples pom.xml

Signed-off-by: jamesbw <github+jamesbw@squareup.com>
added services jar to examples script classpath

Signed-off-by: jamesbw <github+jamesbw@squareup.com>