[Snyk] Security upgrade webpack from 2.7.0 to 4.0.0

[kmaida]

This PR was automatically created by Snyk using the credentials of a real user.

Snyk has created this PR to fix one or more vulnerable packages in the `npm` dependencies of this project.

#### Changes included in this PR - Changes to the following files to upgrade the vulnerable dependencies to a fixed version: - demo/package.json - demo/package-lock.json #### Vulnerabilities that will be fixed ##### With an upgrade: Severity | Priority Score (*) | Issue | Breaking Change | Exploit Maturity :-------------------------:|-------------------------|:-------------------------|:-------------------------|:-------------------------  | **658/1000**
**Why?** Proof of Concept exploit, Recently disclosed, Has a fix available, CVSS 5.3 | Regular Expression Denial of Service (ReDoS)
[SNYK-JS-SEMVER-3247795](https://snyk.io/vuln/SNYK-JS-SEMVER-3247795) | Yes | Proof of Concept (*) Note that the real score may have changed since the PR was raised.

Commit messages

Package name: webpack

The new version differs by 250 commits.

• 213226e 4.0.0
• fde0183 Merge pull request #6081 from webpack/formating/prettier
• b6396e7 update stats
• f32bd41 fix linting
• 5238159 run prettier on existing code
• 518d1e0 replace js-beautify with prettier
• 4c25bfb 4.0.0-beta.3
• dd93716 Merge pull request #6296 from shellscape/fix/hmr-before-node-stuff
• 7a07901 Merge pull request #6563 from webpack/performance/assign-depth
• c7eb895 Merge pull request #6452 from webpack/update_acorn
• 9179980 Merge pull request #6551 from nveenjain/fix/templatemd
• e52f323 optimize performance of assignDepth
• 6bf5df5 Fixed template.md
• 90ab23a Merge branch 'master' into fix/hmr-before-node-stuff
• b0949cb add integration test for spread operator
• 39438c7 unittest now also walks the ast
• 15ab027 Merge pull request #6536 from jevan0307/sideEffects-selectors
• 1611ce1 Merge pull request #6561 from joshunger/patch-1
• 6e175bc Merge pull request #6549 from webpack/md4_hash
• 0637531 Add a hyperlink to create a new issue
• 0e1f9c6 Merge pull request #6554 from webpack/deps/end-of-beta
• 72477f4 upgrade versions to stable versions
• ed30285 Merge pull request #6546 from webpack/bot/review-permission
• 40ee8c7 Use MD4 for hashing

See the full diff

Check the changes in this PR to ensure they won't cause issues with your project. ------------ **Note:** *You are seeing this because you or someone else with access to this repository has authorized Snyk to open fix PRs.* For more information: 🧐 [View latest project report](https://app.snyk.io/org/kim.maida/project/0521d044-bc71-40e1-9cb6-a0a1b5850079?utm_source=github&utm_medium=referral&page=fix-pr) 🛠 [Adjust project settings](https://app.snyk.io/org/kim.maida/project/0521d044-bc71-40e1-9cb6-a0a1b5850079?utm_source=github&utm_medium=referral&page=fix-pr/settings) 📚 [Read more about Snyk's upgrade and patch logic](https://support.snyk.io/hc/en-us/articles/360003891078-Snyk-patches-to-fix-vulnerabilities) [//]: # (snyk:metadata:{"prId":"dc4b662a-595e-45f9-9a4c-7f3559170525","prPublicId":"dc4b662a-595e-45f9-9a4c-7f3559170525","dependencies":[{"name":"webpack","from":"2.7.0","to":"4.0.0"}],"packageManager":"npm","projectPublicId":"0521d044-bc71-40e1-9cb6-a0a1b5850079","projectUrl":"https://app.snyk.io/org/kim.maida/project/0521d044-bc71-40e1-9cb6-a0a1b5850079?utm_source=github&utm_medium=referral&page=fix-pr","type":"auto","patch":[],"vulns":["SNYK-JS-SEMVER-3247795"],"upgrade":["SNYK-JS-SEMVER-3247795"],"isBreakingChange":true,"env":"prod","prType":"fix","templateVariants":["updated-fix-title","priorityScore"],"priorityScoreList":[658],"remediationStrategy":"vuln"}) --- **Learn how to fix vulnerabilities with free interactive lessons:** 🦉 [Regular Expression Denial of Service (ReDoS)](https://learn.snyk.io/lessons/redos/javascript/?loc=fix-pr)