Support 2b or 2y as indentation by Bcrypt

[afeefghannam89]

We should support 2b or 2y indentation for logstaash user password hashing, when we not support Elasticsearch 7 anymore in this collection. At the moment we support 2a which gut for elasticsearch company is. 2y and 2b are more secure than 2a. We should only make the indentation parameter in the logstash writer user as a variable and put the new value in defaults.yml

Here are the relevant links:
https://passlib.readthedocs.io/en/stable/lib/passlib.hash.bcrypt.html
elastic/elasticsearch#76083