Fix error when file has header rows but no data

Previously the error was saying ‘It needs at least one row of data, and
columns called None’.

app/templates/views/check/column-errors.html

@@ -38,12 +38,18 @@
         <h1 class='banner-title' data-module="track-error" data-error-type="No rows" data-error-label="{{ upload_id }}">
           Your file is missing some rows
         </h1>
-        <p>
-          It needs at least one row of data, and {{ recipients.missing_column_headers | sort() | formatted_list(
-            prefix='a column called',
-            prefix_plural='columns called'
-          ) }}.
-        </p>
+        {% if recipients.missing_column_headers %}
+          <p>
+            It needs at least one row of data, and {{ recipients.missing_column_headers | sort() | formatted_list(
+              prefix='a column called',
+              prefix_plural='columns called'
+            ) }}.
+          </p>
+        {% else %}
+          <p>
+            It needs at least one row of data.
+          </p>
+        {% endif %}
 
       {% elif not recipients.has_recipient_columns %}
 

tests/app/main/views/test_send.py

@@ -352,6 +352,16 @@ def test_upload_csvfile_with_errors_shows_check_page_with_errors(
             'Skip to file contents'
         )
     ),
+    (
+        """
+            phone number, name
+        """,
+        (
+            'Your file is missing some rows '
+            'It needs at least one row of data. '
+            'Skip to file contents'
+        )
+    ),
     (
         "+447700900986",
         (