Use correct capitalization of TeX

test/test_markup.rb

@@ -353,13 +353,13 @@ context "Markup" do
   #
   #########################################################################
 
-  test "tex block syntax" do
+  test "TeX block syntax" do
     content = 'a \[ a^2 \] b'
     output = "<p>a <script type=\"math/tex; mode=display\">a^2</script> b</p>"
     compare(content, output, 'md')
   end
 
-  test "tex inline syntax" do
+  test "TeX inline syntax" do
     content = 'a \( a^2 \) b'
     output = "<p>a <script type=\"math/tex\">a^2</script> b</p>"
     compare(content, output, 'md')