doc(README.md): fix a broken markdown link

[loveDstyle]

Please Read the CONTRIBUTING Guidelines
In particular the portion on Commit Message Formatting

Please check if the PR fulfills these requirements

• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• [✅ ] Other... Please describe: docs update

What is the current behavior? (You can also link to an open issue here)
due to an extra '(', the link to webpack documentatio is broken

What is the new behavior?
link is working now

Does this PR introduce a breaking change?

• Yes
• [✅ ] No

If this PR contains a breaking change, please describe the following...

• Impact:
• Migration path for existing applications:
• Github Issue(s) this is regarding:

Other information:

[nicolo-ribaudo]

Thanks!