Fix app stuck and memory issues while uploading images (#2287)

* Do not use an image array to store all bitmap pixels at once

* Extract image preprocessing to a different service and use computation thread

* Add java docs

* Cleanup code to remove temp file logic

* Add logs in upload flow

* Fix tests

* Fix more tests

app/src/test/kotlin/fr/free/nrw/commons/utils/FileUtilsTest.kt

@@ -7,17 +7,6 @@ import org.junit.Test
 import java.io.*
 
 class FileUtilsTest {
-    @Test
-    fun copiedFileIsIdenticalToSource() {
-        val source = File.createTempFile("temp", "")
-        val dest = File.createTempFile("temp", "")
-        writeToFile(source, "Hello, World")
-
-        FileUtils.copy(FileInputStream(source), FileOutputStream(dest))
-
-        assertEquals(getString(source), getString(dest))
-    }
-
     @Test
     fun deleteFile() {
         val file = File.createTempFile("testfile", "")