emacs/show: restrict inlined mimetypes on refresh.

This fixes the bug reported by Al [1]. Essentially apply the same fix
as [2] in a different place.

[1]: id:877d41nmr1.fsf@gmail.com
[2]: 90a7c1af36

emacs/notmuch-show.el

@@ -1528,6 +1528,7 @@ non-nil) then the state of the buffer (open/closed messages) is
 reset based on the original query."
   (interactive "P")
   (let ((inhibit-read-only t)
+	(mm-inline-override-types (notmuch--inline-override-types))
 	(state (unless reset-state
 		 (notmuch-show-capture-state))))
     ;; `erase-buffer' does not seem to remove overlays, which can lead

test/T450-emacs-show.sh

@@ -339,7 +339,6 @@ EOF
 test_expect_equal_file EXPECTED OUTPUT
 
 test_begin_subtest "tar not inlined by default on refresh"
-test_subtest_known_broken
 test_emacs '(notmuch-show "id:874llc2bkp.fsf@curie.anarc.at")
 	   (notmuch-show-refresh-view)
 	(test-visible-output "OUTPUT")'