fix(build): Use Node 14 in "Size Check" job to fix CI runs on master

[Lms24]

Since we re-enabled the "Size Check" job for GHA runs on master in #5314, our CI runs were failing because the "Size Check" job was failing. The reason is that our size-limit-action is not passing on the skip_step option we set here

sentry-javascript/.github/workflows/build.yml

Line 210 in 05cb748

skip_step: build

if it is executed on the master branch. Instead, null is passed to the execution function of the action which makes the action first call yarn install followed by yarn build. This fails because the Ember SDK cannot be built with Node 16.

While the best option to fix this is to make changes to the actions to respect the skip_step option on master runs, we want to fix things on our end for now which should work by setting the Node version to 14.

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser - ES5 CDN Bundle (gzipped + minified)	19.3 KB (added)
@sentry/browser - ES5 CDN Bundle (minified)	59.72 KB (added)
@sentry/browser - ES6 CDN Bundle (gzipped + minified)	17.9 KB (added)
@sentry/browser - ES6 CDN Bundle (minified)	52.67 KB (added)
@sentry/browser - Webpack (gzipped + minified)	19.67 KB (added)
@sentry/browser - Webpack (minified)	64.04 KB (added)
@sentry/react - Webpack (gzipped + minified)	19.69 KB (added)
@sentry/nextjs Client - Webpack (gzipped + minified)	43.85 KB (added)
@sentry/browser + @sentry/tracing - ES5 CDN Bundle (gzipped + minified)	25.63 KB (added)
@sentry/browser + @sentry/tracing - ES6 CDN Bundle (gzipped + minified)	23.9 KB (added)