Update garbage-collection.md (#3110)

datacenter/dtr/2.2/guides/admin/configure/garbage-collection.md

@@ -20,9 +20,9 @@ The GC cron schedule is set to run in **UTC time**.  Containers typically run in
 UTC time (unless the system time is mounted), therefore remember that the cron
 schedule will run based off of UTC time when configuring.
 
-GC puts DTR into read only mode; pulls succeed while pushes fail.  Pushing an
+GC puts DTR into read-only mode; pulls succeed while pushes fail. Pushing an
 image while GC runs may lead to undefined behavior and data loss, therefore
-this is disabled for safety.  For this reason it's generally best practice to
+this is disabled for safety. For this reason, it's generally best practice to
 ensure GC runs in the early morning on a Saturday or Sunday night.
 
 
@@ -52,7 +52,7 @@ the schedule ("Save") or save the schedule *and* start GC immediately ("Save
 
 ## Stopping GC while it's running
 
-When GC runs the garbage collection settings page looks as follows:
+When GC runs the garbage collection, the settings page looks as follows:
 
 ![](../../images/garbage-collection-3.png){: .with-border}
 
@@ -70,7 +70,7 @@ pushes work as expected.
 Each image stored in DTR is made up of multiple files:
 
 - A list of "layers", which represent the image's filesystem
-- The "config" file, which dictates the OS, architecture and other image
+- The "config" file, which dictates the OS, architecture, and other image
 metadata
 - The "manifest", which is pulled first and lists all layers and the config file
 for the image.