Add 3.8.7 release notes

Change-Id: I4efd8b794ad5e71f1646dadefcfcc647574fec74

pages/site/releases/3.8.md

diff --git a/pages/site/releases/3.8.md b/pages/site/releases/3.8.md
index 4581c03..a39ec73 100644
--- a/pages/site/releases/3.8.md
+++ b/pages/site/releases/3.8.md
@@ -723,6 +723,16 @@
 
 ## Bugfix releases
 
+### 3.8.7 (In Development)
+
+* Enhancements
+
+* Bug Fixes
+
+* Plugin changes
+
+* Security Fixes
+
 ### 3.8.6
 
 * Enhancements