Implement Config Files validations and Cargo Nextest for testing in CI pipeline

[JMTamayo]

This pull request includes several changes to the CI pipeline, configuration files, and documentation. The main objectives are to enhance the CI pipeline, improve project configuration, and update documentation. Below are the most important changes:

CI Pipeline Enhancements:

• Added a scheduled job to run the CI pipeline every Sunday at 05:00 UTC. (.github/workflows/CI.yml)
• Refactored the CI pipeline to split the process into Project-Config, Docs, Build, Tests, and Security steps. (.github/workflows/CI.yml)
• Introduced cargo-nextest for running unit tests alongside llvm-cov. (Makefile) [1] [2]

Configuration Improvements:

• Added configuration for yamlfmt and taplo to verify YAML and TOML files format. (.github/workflows/CI.yml, .yamlfmt.yaml, Makefile) [1] [2] [3]
• Simplified the Cargo.toml and deny.toml files by consolidating entries into single lines. (Cargo.toml, deny.toml, redsumer-rs/Cargo.toml) [1] [2] [3]

Documentation Updates:

• Updated CHANGELOG.md to reflect the new CI pipeline steps and added new tools for verifying project configuration. (CHANGELOG.md)

Code Documentation Enhancements:

• Improved inline documentation by adding backticks around code identifiers in comments. (redsumer-rs/src/core/streams/consumer.rs, redsumer-rs/src/redsumer/consumer.rs) [1] [2] [3]