Revert "Consistent pg_connection alias usage"

This reverts commit e3d7941.

Author: tammy-baylis-swi

instrumentation/opentelemetry-instrumentation-psycopg/src/opentelemetry/instrumentation/psycopg/__init__.py

@@ -162,7 +162,7 @@ def _instrument(self, **kwargs):
 
         dbapi.wrap_connect(
             __name__,
-            pg_connection,  # pylint: disable=no-member
+            psycopg.Connection,  # pylint: disable=no-member
             "connect",
             self._DATABASE_SYSTEM,
             self._CONNECTION_ATTRIBUTES,
@@ -189,7 +189,7 @@ def _uninstrument(self, **kwargs):
         """ "Disable Psycopg instrumentation"""
         dbapi.unwrap_connect(psycopg, "connect")  # pylint: disable=no-member
         dbapi.unwrap_connect(
-            pg_connection,
+            psycopg.Connection,
             "connect",  # pylint: disable=no-member
         )
         dbapi.unwrap_connect(