template add-id minor fix, metanorma/metanorma-itu#605

xslt_src/common.xsl

@@ -19497,7 +19497,7 @@
 			<!-- add @id - first element with @id plus '_element_name' -->
 			<xsl:variable name="prefix_id_" select="(.//*[@id])[1]/@id"/>
 			<xsl:variable name="prefix_id"><xsl:value-of select="$prefix_id_"/><xsl:if test="normalize-space($prefix_id_) = ''"><xsl:value-of select="generate-id()"/></xsl:if></xsl:variable>
-			<xsl:variable name="document_suffix" select="ancestor::itu:itu-standard/@document_suffix"/>
+			<xsl:variable name="document_suffix" select="ancestor::*[contains(local-name(), '-standard')]/@document_suffix"/>
 			<xsl:attribute name="id"><xsl:value-of select="concat($prefix_id, '_', local-name(), '_', $document_suffix)"/></xsl:attribute>
 		</xsl:if>
 	</xsl:template>