fix: fix kokoro windows java8 ci (#2573)

* chore: fix kokoro windows java8 ci

* chore: update version

* chore: update file

* 🦉 Updates from OwlBot post-processor

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Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: harshachinta

.kokoro/build.bat

@@ -15,8 +15,4 @@
 :: downstream client libraries before they are released.
 :: See documentation in type-shell-output.bat
 
-set JAVA8_HOME=%JAVA_HOME:"=%
-choco install -y openjdk11
-set JAVA11_HOME=C:\Program Files\Eclipse Adoptium\jdk-11.0.18.10-hotspot\
-
 "C:\Program Files\Git\bin\bash.exe" %~dp0build.sh