[16.0] sale_quotation_number : wrong behavior when you change sale.quotation sequence prefix

[menadz]

Module

sale_quotation_number

Describe the bug

In the sequences configuration, i set the sale quotation prefix to something different than "SQ", when i create a quotation, it will keep the same sequence as when i confirm the quotation

I found out that this module works only if the sale.quotation prefix start with "SQ" (SQI, SQO, SQS for example works too)

To Reproduce

Affected versions: 16.0

Steps to reproduce the behavior:

1. in Sales -> Configuration : uncheck ‘Use same enumeration for quotations and sale orders’
2. General Settings -> Technical -> Sequence
3. Search for sale.quotation sequence and open it
4. Change the prefix to something different to default value (SQ) :

5. Create a sale quotation
6. Confirm the sale quotation

Expected behavior
1.Create a sale quotation with the following sequence FP0001
2.Confirm the sale quotation to a sale order and get the its proper sequence (SO0001)

[simoneversienti]

There's a similar issue here: #2756