Explicitly finalize job process pool and attributes.

Resolved issue about processes on the job pool not exiting when "exit"
command executed from the main process, leaving tmp directories
un-deleted.
Added signal handler explicitly on SIGTERM and __exit__() method to
delete tmp directories on exiting.

Test: > fetch <>, exit
Bug: 73850039
Change-Id: I07be53cdacb64c5cde0c368e0e9ccd2922ae63d3
1 file changed
tree: 8ea8176eeec89cecb8431b2ccf14bc4909d97c22
  1. harnesses/
  2. host_setup/
  3. .clang-format
  4. .gitignore
  5. OWNERS