Try to make instrumentation test work

* Add `Class.forName("org.sqlite.JDBC")`
* Add some logging
* Do not use `java.nio.file`-API

mailbox-android/src/androidTest/java/org/briarproject/mailbox/core/DatabaseCreationTest.kt

 package org.briarproject.mailbox.core
 
+import android.util.Log
 import kotlinx.coroutines.runBlocking
 import org.junit.Test
 import org.sqlite.mc.SQLiteMCConfig
-import java.nio.file.Files
-import java.nio.file.Path
+import java.io.File
 import java.sql.Connection
 import java.sql.DriverManager
 import kotlin.test.assertEquals
@@ -12,10 +12,16 @@ import kotlin.test.assertTrue
 
 class DatabaseCreationTest {
 
+    companion object {
+        val LOG_TAG = "db test"
+    }
+
     @Test
     fun createDatabase(): Unit = runBlocking {
-        val file: Path = Files.createTempFile("test", ".sqlite")
-        println(file)
+        Class.forName("org.sqlite.JDBC")
+
+        val file: File = File.createTempFile("test", ".sqlite")
+        Log.i(LOG_TAG, "file: $file")
         val connection: Connection = DriverManager.getConnection(
             "jdbc:sqlite:$file",
             SQLiteMCConfig().withKey("very-secret").toProperties()
@@ -46,7 +52,7 @@ class DatabaseCreationTest {
             }
         }
 
-        Files.delete(file)
+        file.delete()
     }
 
 }