Enable Isolated Projects for the project self (#1984)

* Initial plan

* Enable Isolated Projects for the shadow plugin project's own build

Co-authored-by: Goooler <10363352+Goooler@users.noreply.github.com>

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Goooler <10363352+Goooler@users.noreply.github.com>

Author: Copilot

gradle.properties

@@ -9,6 +9,7 @@ org.gradle.jvmargs=-Dfile.encoding=UTF-8 -Xmx4g
 org.gradle.kotlin.dsl.allWarningsAsErrors=true
 org.gradle.parallel=true
 org.gradle.tooling.parallel=true
+org.gradle.unsafe.isolated-projects=true
 
 ########## Properties for publishing to Maven Central ##########