Fix postcss vulernerabilities, Bump PostCSS to 8.4.38, resolving CVE-2023-44270 #14

CVEs: [CVE-2023-44270]

Description: An issue was discovered in postcss versions prior to 8.4.31. The vulnerability affects linters using PostCSS to parse external untrusted CSS. An attacker can prepare CSS in such a way that it will contains parts parsed by PostCSS as a CSS comment. After processing by PostCSS, it will be included in the PostCSS output in CSS nodes (rules, properties) despite being included in a comment.

PostCSS to 8.4.38