chore(packages): Bump version of react-scripts used by demo-app-ts to prevent node-gyp errors on yarn install

[mturley]

For some reason, on my machine when running yarn install after #4076 was merged I was getting failures related to node-gyp trying to compile an old version of fsevents (1.2.4), which does not have prebuilt binaries available for macOS. yarn why fsevents found that the only reason we depend on fsevents@1.2.4 is because we're on an old version of react-scripts in packages/react-integration/demo-app-ts.

This PR bumps that version of react-scripts (which should have no real impact as long as integration tests still run), and yarn install no longer needs to compile fsevents on my machine. No more errors, and a faster install time :)

Thanks @redallen for the help troubleshooting this.

[redallen]

Thanks @mturley for your patience! LGTM

[patternfly-build]

PF4 preview: https://patternfly-react-pr-4092.surge.sh
A11y report: https://patternfly-react-pr-4092-coverage.surge.sh

[dlabrecq]

Looks fine, but the tests are failing

[mturley]

Just rebased and pushed a commit that should fix the build_demo_app CI failure, but I'm not sure why the test_jest_pf4 one was failing. Let's see what happens this time.

[mturley]

Hm.

[mturley]

@redallen bizarrely enough, I'm not able to locally reproduce the build failures CircleCI is showing here, and I am now able to install/build on the existing v4 branch perfectly fine (no longer seeing the node-gyp errors that led me to open this PR in the first place). Maybe we should just close this.. but I am thoroughly confused, would love to figure out wtf is happening.

[mturley]

I'm just going to close this, things seem to be working fine now.