Describe the bug

When 2 breakpoints are encountered in pytest with pudb set up, this error pops: Debugger instance already exists

To Reproduce

Steps to reproduce the behavior:

1. install pudb and pytest in venv
2. create this test.py

def test_foo():
    breakpoint()
    breakpoint()

4. pytest --pdbcls pudb.debugger:Debugger --pdb --capture=no test.py (following https://documen.tician.de/pudb/starting.html#usage-with-pytest)
5. First breakpoint is encountered in pudb, press c to continue to second one
6. See error

Expected behavior

The debugger should be called on second breakpoint

Versions

pudb 2022.1.3