ci: remove Travis configs #4435
Merged
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Summary:
Some time between 13:41 and 17:20 Pacific time today, Travis stopped
even pretending to run our builds. Note: #4433 reports a Travis status,
whereas #4434 has no such item, not even “pending”. And our Travis
dashboard shows no builds more recent than #4433, either.
Relevant Hacker News: https://news.ycombinator.com/item?id=25338983
Thankfully, we finally landed #2953 on Friday, so we are no longer
dependent on Travis. This patch deletes the Travis configs and excises
all remaining mentions.
Test Plan:
Running
git grep -i travisnow fails.wchargin-branch: ci-rm-travis