Remove `discard`, `remove`, and `pop` allowance for `loop-iterator-mutation` #30690

Job	Run time
mkdocs	2m 34s
Determine changes	11s
cargo fmt	15s
pre-commit	34s
python package	1m 11s
cargo build (msrv)	2m 56s
cargo clippy	1m 45s
benchmarks	4m 32s
cargo build (release)	4m 50s
cargo fuzz	4m 28s
cargo shear	23s
cargo test (linux)	3m 20s
cargo test (windows)	7m 11s
cargo test (wasm)	1m 4s
formatter instabilities and black similarity	0s
test scripts	54s
ecosystem	9m 15s
test ruff-lsp	19s
Fuzz the parser	0s
	45m 42s

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