update: juggler to version including security fix.

Author: virkt25

package.json

@@ -49,7 +49,7 @@
  "inflection": "^1.6.0",
  "isemail": "^2.2.1",
  "loopback-connector-remote": "^3.0.0",
- "loopback-datasource-juggler": "^3.9.3",
+ "loopback-datasource-juggler": "^3.15.0",
  "loopback-filters": "^1.0.0",
  "loopback-phase": "^3.0.0",
  "nodemailer": "^2.5.0",