Fix simp tagging

[loefflerd]

Fix a mess I created with #28690

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[github-actions]

PR summary ee1b32ba2b

Import changes exceeding 2%

%	File
+119.50%	Mathlib.NumberTheory.TsumDivsorsAntidiagonal

Import changes for modified files

Dependency changes

File	Base Count	Head Count	Change
Mathlib.NumberTheory.TsumDivsorsAntidiagonal	723	1587	+864 (+119.50%)

Import changes for all files

Files	Import difference
Mathlib.NumberTheory.TsumDivsorsAntidiagonal	864

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Declarations diff

+ norm_natCast
+ sigma_eq_sum_div
+ summable_divisorsAntidiagonal_aux
+ summable_mul_tendsto_const
+ summable_norm_pow_mul_geometric_div_one_sub
+ summable_prod_mul_pow
+ tprod_congr₂
+ tsum_pow_div_one_sub_eq_tsum_sigma
+ tsum_prod_pow_eq_tsum_sigma

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).