ci: add folding markers to avoid getting output out of sections

Move commands to existing sections, or add markers for new sections when
no surrounding existing section is relevant. This is to avoid having
logs outside of subsection for the “vmtest” step of the GitHub action.

travis-ci/vmtest/run_vmtest.sh

@@ -35,11 +35,13 @@ else
   ${VMTEST_ROOT}/prepare_selftests.sh
 fi
 
+travis_fold start adduser_to_kvm "Add user ${USER}"
+sudo adduser "${USER}" kvm
+travis_fold stop adduser_to_kvm
+
 # Escape whitespace characters.
 setup_cmd=$(sed 's/\([[:space:]]\)/\\\1/g' <<< "${VMTEST_SETUPCMD}")
 
-sudo adduser "${USER}" kvm
-
 if [[ "${KERNEL}" = 'LATEST' ]]; then
   if [[ "$CHECKOUT_KERNEL" == "1" ]]; then
     sudo -E sudo -E -u "${USER}" "${VMTEST_ROOT}/run.sh" -b travis-ci/vmtest/bpf-next -o -d ~ -s "${setup_cmd}" ~/root.img