tuna: Adapt show_threads cgroup output to terminal size

Passing the --cgroup flag to the show_threads command currently displays
long cgroup strings on the thread output and decreases readability.

Adapt the show_threads output to account for output string and terminal
size, and format output accordingly to improve readability. Add
--spaced flag to show_threads to print cgroups with spacing in
between thread outputs.

Signed-off-by: Leah Leshchinsky <lleshchi@redhat.com>

target branch: main

Signed-off-by: John Kacur <jkacur@redhat.com>
2 files changed