Reproducible build: use a proper file name for the apk (again).

Part of #418.

build.gradle

@@ -104,7 +104,7 @@ android {
     productFlavors {
         nightly {
             dimension 'version'
-            applicationIdSuffix '.nightly'
+            applicationId 'de.dennisguse.opentracks.nightly'
             signingConfig signingConfigs.nightly
         }
         irreproducible {
@@ -126,13 +126,13 @@ android {
         variant.resValue 'string', 'applicationId', variant.applicationId
 
         variant.outputs.configureEach {
-            if (variant.buildType.name == 'reproducible') {
-                outputFileName = "${applicationId}_${variant.buildType.name}_${variant.versionName}.apk"
+            if (variant.flavorName == 'reproducible') {
+                outputFileName = "${applicationId}_${variant.versionName}.apk"
             } else {
-                outputFileName = "${applicationId}_${variant.buildType.name}_${variant.versionCode}.apk"
+                outputFileName = "${applicationId}_${variant.versionCode}.apk"
             }
 
-            if (variant.buildType.name == 'nightly') {
+            if (variant.flavorName== 'nightly') {
                 setVersionCodeOverride(getVersionCode())
                 setVersionNameOverride(getVersionName())
             }