Update code block syntax in troubleshooting guide

Author: Mauricio

support/azure/virtual-machines/linux/troubleshoot-red-hat-os-upgrade-issues.md

@@ -613,7 +613,7 @@ If you run the Leapp upgrade from RHEL 8.10 to 9.4 or 9.5, the upgrade process m
 
 This issue may be caused by the following setting in `/etc/default/grub`:
 
-```bash
+```config
 GRUB_DEFAULT=0
 ```
 Since `GRUB_DEFAULT=0` forces the system to always boot the first menu entry in GRUB, it skips the Leapp upgrade entry and continues booting into the existing RHEL 8.10 environment.
@@ -625,9 +625,12 @@ Since `GRUB_DEFAULT=0` forces the system to always boot the first menu entry in
 
 > [!NOTE]
 > In this example, `GRUB_DEFAULT` is set to `0`, but in your environment, it might be `1` or another number. Ensure you replace it accordingly in the `sed` command.
-```
+
+
+```bash
 sudo sed -i 's/^GRUB_DEFAULT=0/GRUB_DEFAULT=saved/' /etc/default/grub
 ```
+
 2. Regenerate the GRUB configuration:
 
 **GEN 1:**
@@ -644,7 +647,7 @@ grub2-mkconfig -o /boot/efi/EFI/redhat/grub.cfg
 
 3. Reboot the VM thru the serial console.
 
-```
+```bash
 sudo reboot
 ```