example on how to automate metadata removal without error/warning
Add the following files in your workspace/git
manifest/destruct.xml manifest/destructiveChanges.xml
In the destructiveChanges, list all the metadata that should be removed during deployment (BE CAREFUL)
Launch the following command prior to deployment of your metadata if needed :
sf project deploy start --manifest manifest/destruct.xml --pre-destructive-changes manifest/destructiveChanges.xml -r -g
-r -g : prevent the script to fail if the metadata is already deleted in the org