docs: update README.md removing proguard rules

[ChryssaAliferi]

Ticket

Description

In this PR, we are removing some outdated documentation in the README.MD file regarding Proguard files and Progruard implementation.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Implementation Details

• Changes in the README.MD file

Checklist:

• Version upgraded (project, README, gradle, podspec etc)
• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added unit tests for the code
• I have made corresponding changes to the documentation

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarCloud