LPS-52194

The issue was cause by LPS-40779 the commit "use two fields when indexing a number, so that both sorting and exact search are supported".

Due to we treat structure name as search field (in JournalArticleIndexer.extractDDMContent() method, we add structure name as search field) and when repeatable structure fields might includes multiple values, it will encounter the issue. For example,

If we added two repeatable structure fields when create web content, web content's content is as the following:

<?xml version="1.0"?>
  <root available-locales="en_US" default-locale="en_US">
	  <dynamic-element name="Integer1810" index="0" type="ddm-integer" index-type="keyword">
		  <dynamic-content language-id="en_US"><![CDATA[12]]></dynamic-content>
	  </dynamic-element>
	  <dynamic-element name="Integer1810" index="1" type="ddm-integer" index-type="keyword">
	        	<dynamic-content language-id="en_US"><![CDATA[876]]></dynamic-content>
	     </dynamic-element>
</root>

When index structure name after applying LPS-40779 fix, it will be "Integer1810_languageId_sortable: [12, 876]", this field includes two values in one document. So we need to set multiValued="true" in the "*_sortable" field.

Referring to the following link regarding Defining Fields:
https://cwiki.apache.org/confluence/display/solr/Defining+Fields
multiValued: If true, indicates that a single document might contain multiple values for this field type.

Thanks,
Hai