Skip proguard for CT's buildconfig (#530)

Author: hborisoff

AndroidSDKCore/consumer-proguard-rules.pro

@@ -9,3 +9,6 @@
 # Keep bytebuddy classes.
 -keep class net.bytebuddy.** { *; }
 -dontwarn net.bytebuddy.**
+
+# Reflection is used to get CT version in runtime
+-keep class com.clevertap.android.sdk.BuildConfig { *; }