User hint stop working when adding a custom function key towards an extension

Given 2 users Alice (1001) and Bob (1002)
Given a function key targeting Alice
When Alice calls Bob
Then the BLF is lit
When a custom function key targeting 1001
When I restart Asterisk
When Alice calls Bob
Then the BLF is NOT lit

Adding a custom function key on an extension breaks the user hint.

This bug was introduced in this commit 424df93e9f7f3587fad17be30d5fa91e080602b9 in wazo-confgend

Because custom hints are now generated before user hints and only one hint is generated for each extension.