Fix typo and change word

Author: Relequestual

jsonschema-core.xml

@@ -964,8 +964,8 @@
                     Resolved against the current URI base, it identifies the URI of a schema to use.
                 </t>
                 <t>
-                    As the value of "$ref" is a URI Reference, this allows the posibility to externalise or
-                    shard a schema across multiple files, and provides the ability to validate recursive structures
+                    As the value of "$ref" is a URI Reference, this allows the possibility to externalise or
+                    divide a schema across multiple files, and provides the ability to validate recursive structures
                     through self-reference.
                 </t>
                 <t>