Bump ansys-mapdl-reader from 0.51.14 to 0.51.15 in /requirements (#1322)

Bumps [ansys-mapdl-reader](https://github.com/pyansys/pymapdl-reader) from 0.51.14 to 0.51.15.
- [Release notes](https://github.com/pyansys/pymapdl-reader/releases)
- [Commits](ansys/pymapdl-reader@v0.51.14...v0.51.15)

---
updated-dependencies:
- dependency-name: ansys-mapdl-reader
  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/requirements_docs.txt

@@ -1,5 +1,5 @@
 Sphinx==5.1.1
-ansys-mapdl-reader==0.51.14
+ansys-mapdl-reader==0.51.15
 ansys-sphinx-theme==0.4.2
 grpcio==1.43.0
 imageio-ffmpeg==0.4.7