fix: redefined proguard rules to make Retrofit work for everyone

app/proguard-rules.pro

@@ -21,4 +21,5 @@
 #-renamesourcefileattribute SourceFile
 
 -keepattributes SourceFile, LineNumberTable
--keep public class * extends java.lang.Exception
+-keep public class * extends java.lang.Exception
+-keep class retrofit2.** { *; }