Bump plexapi from 4.15.7 to 4.15.8

Bumps [plexapi](https://github.com/pkkid/python-plexapi) from 4.15.7 to 4.15.8.
- [Release notes](https://github.com/pkkid/python-plexapi/releases)
- [Commits](pkkid/python-plexapi@4.15.7...4.15.8)

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

Signed-off-by: dependabot[bot] <[email protected]>

requirements.txt

@@ -2,7 +2,7 @@ num2words==0.5.13
 numpy==1.26.3
 opencv-python==4.9.0.80
 pillow==10.2.0
-PlexAPI==4.15.7
+PlexAPI==4.15.8
 pmmutils==0.5.10
 requests==2.31.0
 retrying==1.3.4