Yarn version 2 and higher fails to execute happo-ci scripts

[trotzig]

While upgrading to Yarn 4 (from v1.22) I noticed that invoking yarn happo-ci-github-actions would fail with this error:

node_modules/happo.io/bin/happo-ci-github-actions:3
# Make the whole script fail on errors
^
SyntaxError: Invalid or unexpected token

I believe this is because Yarn treats any script as a node javascript file starting from v2. I played around with several workarounds in a PR but eventually gave up. I tried these things:

• Wrap happo-ci-github-actions in a script where I explicitly call bash node_modules/.bin/happo-ci-github-actions. It got past the first error but when a sub script was called I ended up with the same issue just further down the flow of execution.
• Stop using yarn altogether and call the happo-ci-github-actions script directly. Failed similarly.

[trotzig]

I found the best workaround to be to use npx -p happo.io in place of yarn. So turning this

yarn happo-ci-github-actions

to

npx -p happo.io happo-ci-github-actions

To prevent npx from downloading another copy of the happo.io library (which it would do since yarn doesn't store dependencies in the same place as before), I added the following to .yarnrc.yml:

nodeLinker: node-modules

Here's a link to a pull-request where you can look at the changes made:
happo/happo-plugin-storybook#116