Improve common "indentation_size" parameter to be shared by indentation rules in the style checker lint module

Summarizing discussion from from PR https://github.com/intel/dml-language-server/pull/56#discussion_r2101938511 for a possible enhancement to more elegantly share this common parameter among all indentation rules that depend the common indentation size used in a given configuration.

Currently, the value is parsed from either the lint_config.json file or taken from the default LintCfg structure and is copied over from the first indentation rule to the fields in the other rules that make use of it.

A nicer implementation would have a shared value.