CREATE EXTENSION script for postgis_tiger_geocoder should use CREATE FUNCTION

[robe]

Right now it uses CREATE OR REPLACE FUNCTION. However since CREATE EXTENSION there should be none of these functions existing, it should do a CREATE FUNCTION instead to prevent overwriting of user functions and also hacker exploits.

This is breaking it out of #5165.

[Regina Obe <lr@…>]

In 523502d/git:

Change address_standardizer and postgis_tiger_geocoder
CREATE EXTENSION to use CREATE instead of CREATE OR REPLACE.
References #5195 and #5196 for PostGIS 3.3.0