[fenix] No issue: run detekt on unit test files.

detekt still passes after I make this change.

afaik, there isn't a good reason not to run it on unit tests and it can
be valuable to add custom rules for them. Also, detekt is already
running on our androidTest directory.

build.gradle

@@ -179,7 +179,6 @@ tasks.register('ktlint', JavaExec) {
 
 tasks.withType(io.gitlab.arturbosch.detekt.Detekt.class).configureEach {
     exclude("**/resources/**")
-    exclude("**/test/**")
     exclude("**/tmp/**")
 }