Update checkout actions

[saghul]

Fixes: #292

[saghul]

Ha, the gcc48 job fails with:

/__e/node20/bin/node: /lib/x86_64-linux-gnu/libm.so.6: version `GLIBC_2.27' not found (required by /__e/node20/bin/node)
/__e/node20/bin/node: /usr/lib/x86_64-linux-gnu/libstdc++.so.6: version `GLIBCXX_3.4.20' not found (required by /__e/node20/bin/node)
/__e/node20/bin/node: /usr/lib/x86_64-linux-gnu/libstdc++.so.6: version `CXXABI_1.3.9' not found (required by /__e/node20/bin/node)
/__e/node20/bin/node: /usr/lib/x86_64-linux-gnu/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by /__e/node20/bin/node)
/__e/node20/bin/node: /lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.28' not found (required by /__e/node20/bin/node)
/__e/node20/bin/node: /lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.25' not found (required by /__e/node20/bin/node)

I kept it on v3 for now. The job could probably be rewritten to run on a container with the checked out code mounted or something... leaving that for later.