build.gradle: update versionCode to match playstore (#805)

updates #cleanup

Manual bump to fix Fdroid

Signed-off-by: kari-ts <kari@tailscale.com>

Author: kari-ts

android/build.gradle

@@ -37,7 +37,7 @@ android {
     defaultConfig {
         minSdkVersion 26
         targetSdkVersion 35
-        versionCode 468
+        versionCode 615
         versionName getVersionProperty("VERSION_LONG")
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"