refactor(tap-agent): use insta for snapshot testing messages

[TypeLevelConsoli]

Add insta for snapshot testing messages instead of constructing the expected result.

Insta will automatically compare the message with the snapshot during just test (or cargo test, cargo nextest run), and fail if the message diverges.

To review changes, it's recommended to use cargo-insta CLI, but it's not necessarily needed.

Please, read the create Getting started docs for a introduction to the recommended workflow: https://insta.rs/docs/quickstart/

[github-actions]

Pull Request Test Coverage Report for Build 13950511037

Details

• 7 of 7 (100.0%) changed or added relevant lines in 2 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.02%) to 76.225%

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Files with Coverage Reduction	New Missed Lines	%
crates/tap-agent/src/agent/sender_account.rs	1	76.89%

Totals
Change from base Build 13905755288:	-0.02%
Covered Lines:	8416
Relevant Lines:	11041

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💛 - Coveralls