Removed duplicate migration

no issue

- The migration didn't want to go away after rebases combined with renames

core/server/data/migrations/versions/4.0/17-refactor-unsplash-setting.js

@@ -1,33 +0,0 @@
-const logging = require('../../../../../shared/logging');
-const {createIrreversibleMigration} = require('../../utils');
-
-module.exports = createIrreversibleMigration(async (knex) => {
-    const unsplashSetting = await knex('settings')
-        .select('value')
-        .where({
-            key: 'unsplash'
-        })
-        .first();
-
-    let isActive;
-    try {
-        const value = JSON.parse(unsplashSetting.value);
-        isActive = typeof value.isActive === 'boolean' ? value.isActive : true;
-    } catch (err) {
-        logging.warn(`Wasn't able to parse 'unsplash' setting: ${unsplashSetting.value}, falling back to: 'true'`);
-        isActive = true;
-    }
-
-    logging.info(`Updating 'unsplash' setting to: ${isActive}`);
-
-    await knex('settings')
-        .update({
-            group: 'unsplash',
-            type: 'boolean',
-            flags: null,
-            value: isActive.toString()
-        })
-        .where({
-            key: 'unsplash'
-        });
-});