Auto merge of #27481 - Monty0045:master, r=jdm
Auto merge of #27481 - Monty0045:master, r=jdm

Support Linux Mint 20.04 for mach bootstrap

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Adds support for Linux Mint 20.04 (based on Ubuntu 20.04) to mach bootstrap.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors

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