chore: adjust .travis to install latest npm

[kentcdodds]

As recommended by @ljharb https://github.com/testing-library/react-testing-library/pull/809/files#r514441103

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[codecov]

Codecov Report

Merging #812 into master will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##            master      #812   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            4         4           
  Lines          117       117           
  Branches        16        16           
=========================================
  Hits           117       117           

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[nickmccurdy]

Out of curiosity, are we still supporting Node versions that don't support npm 7?

[ljharb]

No, but this way you don’t have to keep track of which npm supports which node.

[kentcdodds]

Thanks @ljharb!

@all-contributors please add @ljharb for review

[allcontributors]

@kentcdodds

I've put up a pull request to add @ljharb! 🎉

[testing-library-bot]

🎉 This PR is included in version 11.1.1 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[nickmccurdy]

FYI: You can use the Add Suggestion button on GitHub (or git commit --author "..." to commit changes manually) to commit something authored by someone else. git/GitHub will display both users on the commit.

[nickmccurdy]

@kentcdodds This installs npm 6, not 7. Is that intentional or should we adjust Travis/actions to use npm 7? Also applies to Vue Testing Library.

[ljharb]

That’s because npm 7 isn’t marked latest yet.

[nickmccurdy]

I'm aware. I wasn't sure if Kent wanted to specifically use 6 or 7, or just have the fix for #809.