Fix duplicate value in snooty.toml

Author: Chris Cho

snooty.toml

@@ -10,7 +10,6 @@ package-branch = "testing"
 package-version = "4.4.0"
 package-name-org = "mongodb-org"
 version = "4.0"
-rst-title = "reStructuredText"
 rst = "reStructuredText"
 rst-abbrev = "RST"
 yaml = "Yet Another Markup Language"

source/style-guide/markup-guidelines.txt

@@ -9,7 +9,7 @@ Markup Guidelines
 This section describes markup conventions for {+rst+} ({+rst-abbrev+}) and
 {+markdown+}.
 
-{+rst-title+} ({+rst-abbrev+})
+{+rst+} ({+rst-abbrev+})
 ~~~~~~~~~~~~~~~~~~~~~~~
 
 MongoDB documentation uses {+rst+} ({+rst-abbrev+}) markup syntax