style(2019-08-06--test_user_with_series_in_collection.xml): tiny formatting improvement.

Should be in 7aaa69e commit.

[skip ci]

Author: php-coder

src/main/resources/liquibase/version/0.4.1/2019-08-06--test_user_with_series_in_collection.xml

@@ -26,7 +26,7 @@
 		</insert>
 
 		<insert tableName="collections_series">
-			<column name="collection_id" valueComputed="(SELECT id FROM collections WHERE slug='seriesowner')" />
+			<column name="collection_id" valueComputed="(SELECT id FROM collections WHERE slug = 'seriesowner')" />
 			<column name="series_id" value="1" />
 			<column name="number_of_stamps" value="1" />
 		</insert>