l10n: Change to a capital letter

Signed-off-by: Valdnet <47037905+Valdnet@users.noreply.github.com>

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

@@ -367,7 +367,7 @@
     <string name="nc_upload_choose_local_files">Choose files</string>
     <string name="nc_upload_confirm_send_multiple">Send these files to %1$s?</string>
     <string name="nc_upload_confirm_send_single">Send this file to %1$s?</string>
-    <string name="nc_upload_in_progess">uploading</string>
+    <string name="nc_upload_in_progess">Uploading</string>
 
     <!-- Phonebook Integration -->
     <string name="nc_settings_phone_book_integration_key" translatable="false">phone_book_integration</string>