The procedure for uninstalling MySQL Workbench on Linux depends on the packe you are using.
Uninstalling DEB packages
For Debian packages the command is:
shell> sudo dpkg -r mysql-workbench-oss
This does not remove the configuration files. If you wish to also remove the configuration files use:
shell> sudo dpkg --purge mysql-workbench-oss
Uninstalling RPM packages
To uninstall RPM packages use:
shell> sudo rpm -e mysql-workbench-oss
This does not remove the configuration files.