Dependencies: Bump zensical from 0.0.14 to 0.0.15 (#667)

Bumps [zensical](https://github.com/zensical/zensical) from 0.0.14 to 0.0.15.
- [Release notes](https://github.com/zensical/zensical/releases)
- [Commits](zensical/zensical@v0.0.14...v0.0.15)

---
updated-dependencies:
- dependency-name: zensical
  dependency-version: 0.0.15
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements.txt

@@ -1,4 +1,4 @@
 # This file contains the direct dependencies required for building the docs
 # To install them all run 'pip install -r requirements.txt' in the same directory
 
-zensical == 0.0.14
+zensical == 0.0.15