chore(deps): update dependency postcss to v7.0.39

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
postcss (source)	7.0.35 -> 7.0.39

---

Release Notes

postcss/postcss

v7.0.39

Compare Source

• Reduce package size.
• Backport nanocolors to picocolors migration.

v7.0.38

Compare Source

• Update Processor#version.

v7.0.37

Compare Source

• Backport chalk to nanocolors migration.

v7.0.36

Compare Source

• Backport ReDoS vulnerabilities from PostCSS 8.

---

Configuration

📅 Schedule: At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• If you want to rebase/retry this PR, click this checkbox.

---

This PR has been generated by WhiteSource Renovate. View repository job log here.