Update Mockito version to fix error regarding mocking final classes (issue #77)

Author: Fernanda Reis

app/build.gradle

@@ -66,7 +66,7 @@ dependencies {
     kapt "com.google.dagger:dagger-compiler:$dagger_version"
 
     testImplementation 'junit:junit:4.13.2'
-    testImplementation 'org.mockito:mockito-core:3.4.6'
+    testImplementation 'org.mockito:mockito-core:5.3.1'
     testImplementation 'android.arch.core:core-testing:1.1.1'
 
     def androidx_test_version = "1.4.0"