Please remove datasource reference
<resource-ref>
<description>Dashboard Builder Datasource</description>
<res-ref-name>jdbc/dashbuilder</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>

from dashbuilder/WEB-INF/web.xml, as it points to non-existing datasource. Take a look at bug 1047807, comment 11 for more detailed information.