Bump knex from 0.14.6 to 0.19.5

Bumps [knex](https://github.com/tgriesser/knex) from 0.14.6 to 0.19.5.
- [Release notes](https://github.com/tgriesser/knex/releases)
- [Changelog](https://github.com/knex/knex/blob/master/CHANGELOG.md)
- [Commits](knex/knex@0.14.6...0.19.5)

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -43,7 +43,7 @@
     "eslint": "^4.18.0",
     "eslint-config-airbnb-base": "^13.0.0",
     "eslint-plugin-import": "^2.13.0",
-    "knex": "^0.14.4",
+    "knex": "^0.19.5",
     "mocha": "^3.5.0",
     "mysql": "^2.16.0",
     "nyc": "^11.1.0",