Fix README documentation of the one-line make command install

Author: jaxtonw

README.md

@@ -46,7 +46,7 @@ package management system such as RPM to install PostgreSQL, be sure that the
 to find it:
 
 ```sh
-env PG_CONFIG=/path/to/pg_config make && make installcheck && make install
+env PG_CONFIG=/path/to/pg_config make && make install && make installcheck
 ```
 
 If you encounter an error such as:
@@ -138,4 +138,4 @@ particular purpose. The software provided hereunder is on an "as is" basis,
 and The pg-semver Maintainers no obligations to provide maintenance, support,
 updates, enhancements, or modifications.
 
-  [`postgresql.conf` parameters]: https://www.postgresql.org/docs/devel/runtime-config-client.html#RUNTIME-CONFIG-CLIENT-OTHER
+  [`postgresql.conf` parameters]: https://www.postgresql.org/docs/devel/runtime-config-client.html#RUNTIME-CONFIG-CLIENT-OTHER