Fixing old typo in releasenotes

Author: RogerKratz

Src/ReleaseNotes.txt

@@ -8,7 +8,7 @@
 
 
 
-=== v5.3.0 (v 5.3.2.0), 2020-07-22, NH 5.3.0 ===
+=== v5.3.0 (v 5.3.0.0), 2020-07-22, NH 5.3.0 ===
 
 ** Bug
 * #24 Discriminator's insert attribute is not respected