[Doc]: Switch to PGPRO10: autocommit based on 830a345 (doc/ only)

Author: Liudmila Mantrova

doc/src/sgml/contrib.sgml

@@ -132,7 +132,6 @@ CREATE EXTENSION <replaceable>module_name</> FROM unpackaged;
  &lo;
  &ltree;
  &mchar;
- &multimaster;
  &online-analyze;
  &pageinspect;
  &passwordcheck;