fix: ensure the clashing X[i] notation has the same precedence

[eric-wieser]

I don't exactly know why core has :max for GetElem, but not doing so here makes the errors more confusing when both notations are available.

This is needed to make

import Mathlib

open scoped ProbabilityTheory

example (l : List (Fin 3 → ℕ)) (i) (hi : i < l.length) (j : Fin 3) : 0 ≤ l[i] j := sorry

be legal.

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[github-actions]

PR summary 19847b366e

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

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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).