[dependabot]: Bump com.android.tools.build:gradle from 8.0.0 to 8.9.1 in /packages/pigeon/platform_tests/test_plugin/android (flutter#8955)

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Bumps com.android.tools.build:gradle from 8.0.0 to 8.9.1.

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Author: dependabot[bot]

packages/pigeon/platform_tests/test_plugin/android/build.gradle

@@ -9,7 +9,7 @@ buildscript {
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:8.0.0'
+        classpath 'com.android.tools.build:gradle:8.9.1'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }