[Merged by Bors] - chore: delete unused test file

[grunweg]

This file as added in #29513, but never hooked up to the unit tests. It is thus unused; delete it.

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[github-actions]

PR summary 4e9ce78ebd

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff

No declarations were harmed in the making of this PR! 🐙

You can run this locally as follows

## summary with just the declaration names:
./scripts/declarations_diff.sh <optional_commit>

## more verbose report:
./scripts/declarations_diff.sh long <optional_commit>

The doc-module for script/declarations_diff.sh contains some details about this script.

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No changes to technical debt.

You can run this locally as

./scripts/technical-debt-metrics.sh pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).

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note: file MathlibTest/LintStyle2.lean was removed.
Please create a follow-up pull request adding a module deprecation. Thanks!

[Vierkantor]

bors merge

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

• Build
• Post-Build Step
• Lint style