C# Unit Test Project: In post-build event, identifying is it run by unit test project

Question

I'm using Visual Studio 2017, C# Class Library Project. I've bunch of code in my post-build event of this project. This project is referenced by unit test project. I don't want to run the post build event codes in case of running unit test project. In the post-build event of my library, how do I identify if the build event is invoked because of running unit test or building the library directly?

Another way I was thinking is, to change the $(ConfigurationName) as UnitTest while executing unit tests. I don't know how to change it for referenced projects dynamically.

Edit: Here is my code in library project's post build event.

cd  "$(ProjectDir)"
echo %branch%

if $(ConfigurationName)==Release goto :SKIP
if $(ConfigurationName)==Interactive goto :SKIP

set configfile=$(ProjectDir)Configurations\$(ConfigurationName)-App.config
set sourcedir=$(ProjectDir)$(OutDir)
set destdir=\Program Files\Project\AppServer $(ConfigurationName)\

echo config = %configfile%
echo source = %sourcedir%
echo   dest = %destdir%


echo
echo net stop "Application Server $(ConfigurationName)"        >  %TMP%\$(ConfigurationName)deploy.cmd
echo copy "%sourcedir%*.*" "%destdir%"                                           >> %TMP%\$(ConfigurationName)deploy.cmd
echo copy "%configfile%"  "%destdir%AppServer.exe.config"       >> %TMP%\$(ConfigurationName)deploy.cmd
echo net start "Application Server $(ConfigurationName)"      >> %TMP%\$(ConfigurationName)deploy.cmd 
echo  pause                                                                                 >> %TMP%\$(ConfigurationName)deploy.cmd 
cmd /c elevate %TMP%\$(ConfigurationName)deploy.cmd

goto :EXIT

:SKIP
echo Skipping local deployment for configuration $(ConfigurationName) 

:EXIT