fix: Add a note about checking image checksum (#962)

Author: e-minguez

asciidoc/troubleshooting/troubleshooting-edge-image-builder.adoc

@@ -25,6 +25,7 @@ EIB is used to create custom SUSE Edge images.
 * *Operating system user's sshkeys requires a home folder*: When creating an image with users with sshkeys, the home folder needs to be created as well with `createHomeDir=true`.
 * *Combustion issues*: EIB relies on combustion for the customization of the OS and deployment of all the other SUSE Edge components. This also includes custom scripts being placed in the custom/scripts folder. Note that the combustion process is being executed at `initrd` time, so the system is not completely booted when the scripts are executed.
 * *Podman machine size*: As explained in the <<tips-and-tricks,EIB Tips and Tricks section>>, verify the podman machine has enough CPU/memory to run the EIB container on non-Linux operating systems.
+* *Incorrect image*: Ensure the base image being used is properly downloaded by https://www.suse.com/support/security/download-verification/[verifying the `checksum`]. If you are building the image with <<guides-kiwi-builder-images,kiwi-builder>>, check the sum file generated by the process as well.
 
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