Update the changelog for 1.7.0.3.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=278410982
diff --git a/idea_plugin/resources/META-INF/plugin.xml b/idea_plugin/resources/META-INF/plugin.xml
index aa8e8df..8b4bb1f 100644
--- a/idea_plugin/resources/META-INF/plugin.xml
+++ b/idea_plugin/resources/META-INF/plugin.xml
@@ -12,6 +12,8 @@
 
   <change-notes><![CDATA[
     <dl>
+      <dt>1.7.0.3</dt>
+      <dd>Fixed the plugin on 2019.3 IDEs.</dd>
       <dt>1.7.0.2</dt>
       <dd>Added support for all IDEs after 2017.3.</dd>
       <dt>1.7.0.1</dt>