Lint .travis.yml

[abitrolly]

Fixes warnings from https://config.travis-ci.com/explore

[warn] on jobs.include: deprecated key: "sudo" (The key sudo has no effect anymore.)
[warn] on jobs.include: deprecated key: "sudo" (The key sudo has no effect anymore.)
[warn] on root: deprecated key: "sudo" (The key sudo has no effect anymore.)
[info] on root: the key matrix is an alias for jobs, using jobs
[info] on env: the key matrix is an alias for jobs, using jobs
[info] on root: missing os, using the default "linux"

[asmeurer]

FYI, ever since Travis effectively ended all free jobs, we no longer have Travis running on this repo, and it's very difficult to test any changes to doctr.

[abitrolly]

I see https://docs.travis-ci.com/user/billing-overview/#free-plan - so the credits are already over? Have you tried to contact the support to give you OSS excemption?

[asmeurer]

I haven't. I may try, but unless they also give me an exception for other projects I was using Travis for, I personally won't have any investment in this project any more, at least insofar as Travis support goes (if we add support for other CI(s) that may change).

[abitrolly]

Understood. With a GitHub Actions killing other CI systems, I guess there is not choice anymore than to switch to the platform proposition.

[abitrolly]

It also makes it easier to push docs to other branch. This is how I push a huge static build of fedora packages info https://github.com/abitrolly/fedora-packages-static/blob/8787cbfb0dd0ed957996592465751c2bf7a110ce/.github/workflows/manual.yml#L46-L68

[asmeurer]

I don't think GitHub Actions is to blame for Travis stopping their free tier.

[abitrolly]

But what is the point in using Travis for OSS projects right now? It is so inconvenient, and probably more costly not for OSS as well.