!fixup De-personalize Diagnostic File URLs in Compiled Schemas

- In windows, Paths.get().toFile returns a path with the windows style separator, while the tdml is expecting unix style separators. Using uri.getPath, while it returns unix style separators, causes an error because it returns an absolute path with a leading "/" before the drive letter

DAFFODIL-2195

daffodil-test/src/test/resources/org/apache/daffodil/section06/namespaces/namespaces.tdml

@@ -1009,7 +1009,7 @@
         the
         error messages to specifically mention this file, not just show that
         it was included. -->
-      <tdml:error>subfolder/multi_C_06_nons.dfdl.xsd</tdml:error>
+      <tdml:error>multi_C_06_nons.dfdl.xsd</tdml:error>
     </tdml:errors>
   </tdml:parserTestCase>
 
@@ -2212,7 +2212,7 @@
     <tdml:document><![CDATA[temp]]></tdml:document>
       <tdml:errors>
         <tdml:error>nonExistent</tdml:error>
-        <tdml:error>namespaces/multi_C_13.dfdl.xsd</tdml:error>
+        <tdml:error>multi_C_13.dfdl.xsd</tdml:error>
       </tdml:errors>
   </tdml:parserTestCase>