update outdated / vulnerable packages identified by npm install and n…

…pm audit:

braces  <3.0.3
Severity: high
Uncontrolled resource consumption in braces - GHSA-grv7-fg5c-xmjg
fix available via `npm audit fix`
node_modules/braces

postcss  <8.4.31
Severity: moderate
PostCSS line return parsing error - GHSA-7fh5-64p2-3v2j
fix available via `npm audit fix`
node_modules/postcss

ws  7.0.0 - 7.5.9
Severity: high
ws affected by a DoS when handling a request with many HTTP headers - GHSA-3h5v-q93c-6h6q
fix available via `npm audit fix`
node_modules/ws

3 vulnerabilities (1 moderate, 2 high)

To address all issues, run:
  npm audit fix