FTBFS - test_attach_to_pid* fails

On Ubuntu, but not the same package in Debian, all 5 variants of test_attach_to_pid* fail with

stderr: b'Could not attach to process. If your uid matches the uid of the target\nprocess, check the setting of /proc/sys/kernel/yama/ptrace_scope, or try\nagain as the root user. For more details, see /etc/sysctl.d/10-ptrace.conf\nptrace: Inappropriate ioctl for device.\nTarget \'None\' cannot support this command.\nNo symbol table is loaded. Use the "file" command.\nNo symbol table is loaded. Use the "file" command.\n'

or something similar.

This appears to affect all pydevd versions on all architectures (the riscv64 build "succeeds" because it's nocheck), though I haven't checked whether the error has always been that one.