Correct alias elimination docstring typo

[ChrisRackauckas-Claude]

Summary

• correct reprsenting to representing in the alias-elimination docstring
• restore the repository-wide typos spelling check

Root cause

The typo entered in 0b01708ffb4c545b888f859bdcbc505350f723ef when the zero-variable elimination pass was added. It is already present on master, so unrelated pull requests such as #4744 inherit the spelling-check failure.

Validation

• typos-cli 1.48.0: passed repository-wide
• Runic 1.7.0 --check .: passed repository-wide
• git diff --check: passed

Please ignore this PR until it has been reviewed by @ChrisRackauckas.

[ChrisRackauckas-Claude]

Clean-master CI classification after independent local reproduction:

• Both benchmark failures are the pre-existing MTK/MTKBase runner load-order bug fixed in draft Resolve benchmark MTKBase before runner startup #4747. Clean master exits 1 with a loaded-path mismatch and UndefVarError: analytically_integrated; the exact patched AirspeedVelocity run exits 0 and executes the mtkcompile benchmark.
• Both Catalyst Modeling failures are the pre-existing Catalyst test dependency on non-public AffectSystem internals fixed in draft Test symbolic jump affects through public API Catalyst.jl#1509. The focused test and full symbolic_stoichiometry.jl pass locally on Julia 1.12.6.

These failures are independent of the docstring typo in this PR.