Switch to onBackPressedDispatcher for navigating back

onBackPressed() method has been deprecated

Signed-off-by: Aayush Gupta <aayushgupta219@gmail.com>

app/src/main/java/com/stevesoltys/seedvault/ui/BackupActivity.kt

@@ -23,7 +23,7 @@ abstract class BackupActivity : AppCompatActivity() {
     @CallSuper
     override fun onOptionsItemSelected(item: MenuItem): Boolean = when (item.itemId) {
         android.R.id.home -> {
-            onBackPressed()
+            onBackPressedDispatcher.onBackPressed()
             true
         }
         else -> super.onOptionsItemSelected(item)

app/src/main/java/com/stevesoltys/seedvault/ui/recoverycode/RecoveryCodeActivity.kt

@@ -45,7 +45,7 @@ class RecoveryCodeActivity : BackupActivity() {
     override fun onOptionsItemSelected(item: MenuItem): Boolean {
         return when (item.itemId) {
             android.R.id.home -> {
-                onBackPressed()
+                onBackPressedDispatcher.onBackPressed()
                 true
             }
             else -> super.onOptionsItemSelected(item)

storage/demo/src/main/java/de/grobox/storagebackuptester/restore/DemoSnapshotFragment.kt

@@ -31,7 +31,7 @@ class DemoSnapshotFragment : SnapshotFragment() {
         bottomStub.layoutResource = R.layout.footer_snapshot
         val footer = bottomStub.inflate()
         footer.findViewById<Button>(R.id.button).setOnClickListener {
-            requireActivity().onBackPressed()
+            requireActivity().onBackPressedDispatcher.onBackPressed()
         }
         return v
     }