Query optimization (#235)

* Optimize version queries and decrease some query complexity

* Run formatter

migrations/20210820053031_version-optimization.sql

@@ -0,0 +1,7 @@
+ALTER TABLE versions ADD COLUMN version_type varchar(255) default 'release' NOT NULL;
+
+UPDATE versions SET version_type = (SELECT rc.channel FROM release_channels rc WHERE rc.id = release_channel);
+
+ALTER TABLE versions DROP COLUMN release_channel, ALTER COLUMN version_type DROP DEFAULT;
+
+DROP TABLE release_channels;