[commands] Fix typo in waitUntil docs (NFC) (#4841)

wpilibNewCommands/src/main/java/edu/wpi/first/wpilibj2/command/Commands.java

@@ -105,7 +105,7 @@ public final class Commands {
   }
 
   /**
-   * Constructs a command that does nothing, finishing once a command becomes true.
+   * Constructs a command that does nothing, finishing once a condition becomes true.
    *
    * @param condition the condition
    * @return the command