EducationalOrganization subclassof CivicStructure

Reasonably commonsense ommission being fast-track fixed for
covid-19. Am fixing in core rather than pending due to there not
being any new vocabulary involved (so removing the #2450 file).
Fixes #2450

Author: danbri

data/ext/pending/issue-2540.rdfa

@@ -639,6 +639,7 @@ See also the dedicated [document on the use of schema.org for marking up hotels
       <span class="h" property="rdfs:label">EducationalOrganization</span>
       <span property="rdfs:comment">An educational organization.</span>
        <span>Subclass of: <a property="rdfs:subClassOf" href="http://schema.org/Organization">Organization</a></span>
+       <span>Subclass of: <a property="rdfs:subClassOf" href="http://schema.org/CivicStructure">CivicStructure</a></span>
     </div>
 
     <div typeof="rdfs:Class" resource="http://schema.org/CollegeOrUniversity">