Bump assets/themes/zenburn from `cb746f6` to `7f6fb86`

Bumps [assets/themes/zenburn](https://github.com/colinta/zenburn) from `cb746f6` to `7f6fb86`.
- [Release notes](https://github.com/colinta/zenburn/releases)
- [Commits](cb746f6962...7f6fb86e0d)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

assets/themes/zenburn

@@ -1 +1 @@
-Subproject commit cb746f69624e635f6f4d127fa9244658e690c34b
+Subproject commit 7f6fb86e0dcdd06d3c5181ad1cbe94c970834143