How can I remove the package oracle-java11-installer-local?

Run the following command:

sudo rm -rf /var/cache/oracle-jdk11-installer-local

sudo rm /var/lib/dpkg/info/oracle*
sudo apt purge oracle-java11-installer*
sudo rm /etc/apt/sources.list.d/*java*
sudo apt autoremove

I went to the directory /var/cache/oracle-jdk11-installer-local using the file manager (Nautilus), confirmed it was there and then opened a terminal and typed:

sudo rm -r /var/cache/oracle-jdk11-installer-local 

That seemed to fix it.