Remove BUILD_TIME from build.gradle

Needed for reproducible builds, see #495

app/build.gradle

@@ -15,8 +15,6 @@ android {
         // NOTE: keep in sync with locales_config.xml
         resourceConfigurations += ["en", "ar", "az", "de", "es", "in", "it", "pl", "ru", "ta", "tr",
                                    "uk", "zh-rCN"]
-
-        buildConfigField "long", "BUILD_TIME", System.currentTimeMillis() + "L"
     }
 
     flavorDimensions = ["type"]

app/src/main/java/com/emanuelef/remote_capture/Utils.java

@@ -1478,7 +1478,6 @@ public class Utils {
         return "Build type: " + Utils.getVerifiedBuild(ctx).toString().toLowerCase() +
                 (!PCAPdroid.getInstance().isUsharkAvailable() ? " (withoutUshark)" : "") + "\n" +
                 "Build version: " + BuildConfig.VERSION_NAME + "\n" +
-                "Build date: " + dateFormat.format(new Date(BuildConfig.BUILD_TIME)) + "\n" +
                 "Current date: " + dateFormat.format(new Date()) + "\n" +
                 "Device: " + getDeviceModel() + (rooted ? " (rooted)" : "") + "\n" +
                 "OS version: " + getOsVersion() + "\n";