Replace internal `capitalized` extension

'capitalized(): String' is deprecated. This was never intended as a public API.

build-logic/convention/src/main/kotlin/com/google/samples/apps/nowinandroid/Badging.kt

@@ -35,12 +35,12 @@ import org.gradle.api.tasks.OutputFile
 import org.gradle.api.tasks.PathSensitive
 import org.gradle.api.tasks.PathSensitivity
 import org.gradle.api.tasks.TaskAction
-import org.gradle.configurationcache.extensions.capitalized
 import org.gradle.kotlin.dsl.assign
 import org.gradle.kotlin.dsl.register
 import org.gradle.language.base.plugins.LifecycleBasePlugin
 import org.gradle.process.ExecOperations
 import java.io.File
+import java.util.Locale
 import javax.inject.Inject
 
 @CacheableTask
@@ -107,6 +107,10 @@ abstract class CheckBadgingTask : DefaultTask() {
     }
 }
 
+private fun String.capitalized() = replaceFirstChar {
+    if (it.isLowerCase()) it.titlecase(Locale.getDefault()) else it.toString()
+}
+
 fun Project.configureBadgingTasks(
     baseExtension: BaseExtension,
     componentsExtension: ApplicationAndroidComponentsExtension,