Added sql linter

.gitlab-ci.yml

-image: python:3-buster
+image: python:3-bullseye
+
+linter:
+  before_script:
+    - pip3 install sqlfluff
+  script:
+    - sqlfluff lint --dialect postgres
 
 test:
   before_script:

migrations/00001_create-main-table.sql

 -- Create the `obm_buildings` table
-
-CREATE TABLE public.obm_buildings
-(
-    osm_id integer PRIMARY KEY
-);
-
-ALTER TABLE public.obm_buildings
-    OWNER to postgres;
+CREATE TABLE public.obm_buildings (osm_id integer PRIMARY KEY);
+ALTER TABLE public.obm_buildings OWNER TO postgres;