Fixes language: "following allowing" -> "allowing"

Stops propagation of initially erroneous construct.

Change-Id: I2197de57cbac98e87fb39fa0dca4c691fe5e856f
diff --git a/exercises/boot_from_volume.sh b/exercises/boot_from_volume.sh
index 84ac08f..7478bdf 100755
--- a/exercises/boot_from_volume.sh
+++ b/exercises/boot_from_volume.sh
@@ -16,7 +16,7 @@
 set -o errexit
 
 # Print the commands being run so that we can see the command that triggers
-# an error.  It is also useful for following allowing as the install occurs.
+# an error.  It is also useful for following as the install occurs.
 set -o xtrace