Update build.gradle

[berkcoker]

Changing compileSdkVersion from 27 to 28

[ValentinoG]

This commit resolves the following: ` Task :@voximplant_react-native-foreground-service:verifyReleaseResources FAILED

FAILURE: Build failed with an exception.

• What went wrong: Execution failed for task ':@voximplant_react-native-foreground-service:verifyReleaseResources'.

  java.util.concurrent.ExecutionException: com.android.builder.internal.aapt.v2.Aapt2Exception: Android resource linking failed /home/valentino/Scrivania/Programmazione/progetti-expo/it.spyapp.valentino/SpyApp/node_modules/@voximplant/react-native-foreground-service/android/build/intermediates/res/merged/release/values-v28/values-v28.xml:7: error: resource android:attr/dialogCornerRadius not found. /home/valentino/Scrivania/Programmazione/progetti-expo/it.spyapp.valentino/SpyApp/node_modules/@voximplant/react-native-foreground-service/android/build/intermediates/res/merged/release/values-v28/values-v28.xml:11: error: resource android:attr/dialogCornerRadius not found. /home/valentino/Scrivania/Programmazione/progetti-expo/it.spyapp.valentino/SpyApp/node_modules/@voximplant/react-native-foreground-service/android/build/intermediates/res/merged/release/values/values.xml:2714: error: resource android:attr/fontVariationSettings not found. /home/valentino/Scrivania/Programmazione/progetti-expo/it.spyapp.valentino/SpyApp/node_modules/@voximplant/react-native-foreground-service/android/build/intermediates/res/merged/release/values/values.xml:2715: error: resource android:attr/ttcIndex not found. error: failed linking references. ` Very useful, thank you :100:

[cristianoccazinsp]

Stop hardcoding variables and use project variables instead. Something like this: https://github.com/robinpowered/react-native-vitals/pull/13/commits/26027254d4b30d523f08e41cd9bcd4066c0e681e