guild.members: use context manager for pool conn acquire

litecord/blueprints/guild/members.py

@@ -95,8 +95,7 @@ async def _update_member_roles(guild_id: int, member_id: int, wanted_roles: set)
     # in wanted_roles
     removed_roles = roles - wanted_roles
 
-    conn = await app.db.acquire()
-
+    async with app.db.acquire() as conn:
         async with conn.transaction():
             # add roles
             await app.db.executemany(
@@ -119,8 +118,6 @@ async def _update_member_roles(guild_id: int, member_id: int, wanted_roles: set)
                 [(member_id, guild_id, role_id) for role_id in removed_roles],
             )
 
-    await app.db.release(conn)
-
 
 @bp.route("/<int:guild_id>/members/<int:member_id>", methods=["PATCH"])
 async def modify_guild_member(guild_id, member_id):