Auto merge of #24562 - mnem:fix-bootstrap-ubuntu-19.10, r=jdm
Auto merge of #24562 - mnem:fix-bootstrap-ubuntu-19.10, r=jdm

Update the maximum version of Ubuntu suppported to 19.10

Update bootstrap.py to allow it to run on Ubuntu 19.10

---
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #23881

- [ ] There are tests for these changes OR
- [X] These changes do not require tests because there are no tests for bootstrap.py

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