typo: Double word "in"

Author: nschonni

jsonschema-core.xml

@@ -1027,7 +1027,7 @@
         </section>
         <section title="The JSON Schema Core Vocabulary">
             <t>
-                Keywords declared in in this section, which all begin with "$", make up
+                Keywords declared in this section, which all begin with "$", make up
                 the JSON Schema Core vocabulary.  These keywords are either required in
                 order process any schema or meta-schema, including those split across
                 multiple documents, or exist to reserve keywords for purposes that