TEST-46-HOMED: Ignore "Disk Usage" field as well

This can change between the call to homectl inspect and userdbctl
user so let's ignore it along with the other disk fields.

Fixes #32727

test/units/testsuite-46.sh

@@ -20,7 +20,7 @@ inspect() {
     userdbctl user "$USERNAME" | tee /tmp/b
 
     # diff uses the grep BREs for pattern matching
-    diff -I '^\s*Disk \(Size\|Free\|Floor\|Ceiling\):' /tmp/{a,b}
+    diff -I '^\s*Disk \(Size\|Free\|Floor\|Ceiling\|Usage\):' /tmp/{a,b}
     rm /tmp/{a,b}
 
     homectl inspect --json=pretty "$USERNAME"