ELevate: Fix leapp answer for upgrades to EL9 (#473)

docs/elevate/ELevate-offline-guide.md

@@ -262,7 +262,7 @@ Once you've edited the **leapp_upgrade_repositories.repo** file to match your lo
 * The following fixes from *the /var/log/leapp/leapp-report.txt* file are the most popular fixes for RHEL8-based operating systems:
    ```bash
    sudo sed -i "s/^AllowZoneDrifting=.*/AllowZoneDrifting=no/" /etc/firewalld/firewalld.conf
-   sudo leapp answer --section check_vdo.no_vdo_devices=True
+   sudo leapp answer --section check_vdo.confirm=True
    ```
 
   You might also find the following issue in the **leapp-report** file that can interfere with the migration. Consider removing the file:

docs/elevate/ELevate-quickstart-guide.md

@@ -89,7 +89,7 @@ sudo curl -o /etc/yum.repos.d/CentOS-Base.repo https://el7.repo.almalinux.org/ce
   * For RHEL8-based operating systems:
     ```
     sudo sed -i "s/^AllowZoneDrifting=.*/AllowZoneDrifting=no/" /etc/firewalld/firewalld.conf
-    sudo leapp answer --section check_vdo.no_vdo_devices=True
+    sudo leapp answer --section check_vdo.confirm=True
     ```
 
   Check the [ELevate Frequent Issues](/elevate/ELevate-frequent-issues) page for known and frequent issues and guidance steps to solve them.

docs/elevate/ELevating-CentOS7-to-AlmaLinux-9.md

@@ -183,7 +183,7 @@ After these preparations are completed, you can upgrade your AlmaLinux 8 machine
 * The following fixes from *the /var/log/leapp/leapp-report.txt* file are the most popular fixes for RHEL8-based operating systems:
    ```bash
    sudo sed -i "s/^AllowZoneDrifting=.*/AllowZoneDrifting=no/" /etc/firewalld/firewalld.conf
-   sudo leapp answer --section check_vdo.no_vdo_devices=True
+   sudo leapp answer --section check_vdo.confirm=True
    ```
 
   You might also find the following issue in the **leapp-report** file that can interfere with the upgrade. Consider removing the file: