To specify the type of container to use

You specify the type of container you want to work with in the current workspace, and the tool to use with them, by clicking Window > Preferences > Micro Focus > Containers.

The options you can specify are as follows:

Container type
The type of container you want to work with.
Container executable
The executable to use when performing actions for the specified type of container. The file you specify must exist in a directory specified on the PATH environment variable.

By default this is docker.