Use iterators to parse da_data into sequencer commitments

[yaziciahmet]

Description

Use iterators to parse da_data into sequencer commitments. Reasons:

1. Iterators are more idiomatic to Rust.
2. Rust compiler is able to optimize chained iterators more efficiently.

Linked Issues

• Fixes # (issue, if applicable)
• Related to # (issue)

Testing

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Docs

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 12 lines in your changes missing coverage. Please review.

Project coverage is 75.8%. Comparing base (79eb7c6) to head (ad7fc9d).
Report is 2 commits behind head on nightly.

Files with missing lines	Patch %	Lines
...module-system/sov-modules-stf-blueprint/src/lib.rs	0.0%	12 Missing ⚠️

Additional details and impacted files

Files with missing lines	Coverage Δ
...module-system/sov-modules-stf-blueprint/src/lib.rs	43.8% <0.0%> (-2.6%)	⬇️

... and 2 files with indirect coverage changes