test: add broken test for long names in Emacs notmuch-hello view

Currently, the column alignment in Emacs notmuch-hello is broken for
tags/queries with long names.

test/emacs-hello

@@ -44,4 +44,13 @@ test_emacs "(let ((notmuch-hello-sections
              (test-output))"
 test_expect_equal_file OUTPUT $EXPECTED/notmuch-hello-section-counts
 
+test_begin_subtest "Column alignment for tag/queries with long names"
+test_subtest_known_broken
+tag=a-very-long-tag # length carefully calculated for 80 characters window width
+notmuch tag +$tag '*'
+test_emacs '(notmuch-hello)
+            (test-output)'
+notmuch tag -$tag '*'
+test_expect_equal_file OUTPUT $EXPECTED/notmuch-hello-long-names
+
 test_done

test/emacs.expected-output/notmuch-hello-long-names

@@ -0,0 +1,18 @@
+   Welcome to notmuch. You have 52 messages.
+
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+	  52 inbox           52 unread    
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+	  52 a-very-long-tag       52 inbox                 52 unread 
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