Merge pull request #4954 from sjenning/update-image-gc-default

update image gc default value

Author: mburke5678

admin_guide/garbage_collection.adoc

@@ -121,7 +121,7 @@ settings into consideration:
 
 |`*image-gc-high-threshold*`
 |The percent of disk usage (expressed as an integer) which triggers image
-garbage collection. The default is *90*.
+garbage collection. The default is *85*.
 
 |`*image-gc-low-threshold*`
 |The percent of disk usage (expressed as an integer) to which image garbage
@@ -138,7 +138,7 @@ it does not already exist:
 ----
 kubeletArguments:
   image-gc-high-threshold:
-    - "90"
+    - "85"
   image-gc-low-threshold:
     - "80"
 ----