Exit Code on tlmgr Update Missing

[Naveen M K]

Hi,

Today is 1st day of month and CI will download everything afresh. I had set up to so in GitHub Actions,
where I had set up to install LaTeX on Windows every moth afresh. While, it happened, I happened to 
see a error in the logs 
https://github.com/ManimCommunity/manim/runs/1192033452?check_suite_focus=true#step:10:25 
where it didn't install packages. Note: It downloaded a Prebuild Executable from TinyTeX which was build
before this update on September 30.

===============================================================================
tlmgr itself needs to be updated.
Please do this via either
  tlmgr update --self
or by getting the latest updater for Unix-ish systems:
  http://mirror.ctan.org/systems/texlive/tlnet/update-tlmgr-latest.sh
and/or Windows systems:
  http://mirror.ctan.org/systems/texlive/tlnet/update-tlmgr-latest.exe
Then continue with other updates as usual.
===============================================================================

Now the problem is it should exit with status code 1, if there requires an update. That's it.

Cheers,
Naveen 
@naveen521kk