auto-install-hpp: fix url

6 jobs for stable in 43 minutes and 15 seconds (queued for 1 second)
Name Stage Failure
failed
stable-18.04-build Build
Running after_script
Running after script...
$ mv $DEVEL_HPP_DIR $CI_PROJECT_DIR
Uploading artifacts for failed job
Uploading artifacts...
workspace: found 42407 matching files and directories

Uploading artifacts as "archive" to coordinator... ok
id=100406 responseStatus=201 Created token=59Qydr2e
Cleaning up file based variables
ERROR: Job failed: exit code 1
failed
stable-16.04-build Build
Running after_script
Running after script...
$ mv $DEVEL_HPP_DIR $CI_PROJECT_DIR
Uploading artifacts for failed job
Uploading artifacts...
workspace: found 21776 matching files and directories

Uploading artifacts as "archive" to coordinator... ok
id=100407 responseStatus=201 Created token=kZyoyzy6
Cleaning up file based variables
ERROR: Job failed: exit code 1