Add a string to tell the user to name their multi image set

Author: albendz

app/src/main/java/fr/free/nrw/commons/upload/MultipleUploadListFragment.java

@@ -207,7 +207,7 @@ public boolean onOptionsItemSelected(MenuItem item) {
         switch (item.getItemId()) {
             case R.id.menu_upload_multiple:
                 if (baseTitle.getText().toString().trim().isEmpty()) {
-                    Toast.makeText(getContext(), R.string.add_title_toast, Toast.LENGTH_LONG).show();
+                    Toast.makeText(getContext(), R.string.add_set_name_toast, Toast.LENGTH_LONG).show();
                     return false;
                 }
                 multipleUploadInitiatedHandler.OnMultipleUploadInitiated();

app/src/main/res/values/strings.xml

@@ -56,6 +56,7 @@
   <string name="login_failed_generic">Login failed</string>
   <string name="share_upload_button">Upload</string>
   <string name="multiple_share_base_title">Name this set</string>
+  <string name="add_set_name_toast">Please provide a name for this set</string>
   <string name="provider_modifications">Modifications</string>
   <string name="menu_upload_single">Upload</string>
   <string name="categories_search_text_hint">Search categories</string>