Prevent OOM in ICO due to PNG #2455

Job	Run time
rustfmt	9s
test_toolchains (1.85.0)	31s
clippy	43s
cargo-deny	21s
test_toolchains (beta)	1m 54s
test_toolchains (nightly)	1m 38s
test_avif_decoding	1m 39s
test_features	45s
test_features (avif)	1m 26s
test_features (rayon)	46s
test_features (default)	2m 5s
test_features (exr)	1m 1s
test_features (bmp)	54s
test_features (dds)	1m 5s
test_features (ff)	1m 8s
test_features (ico)	57s
test_features (gif)	48s
test_features (jpeg)	49s
test_features (hdr)	50s
test_features (qoi)	51s
test_features (png)	51s
test_features (webp)	50s
test_features (tga)	1m 0s
test_features (tiff)	56s
test_features (pnm)	50s
test_other_archs (powerpc64-unknown-linux-gnu)	6m 49s
test_other_archs (i686-unknown-linux-gnu)	3m 0s
Fuzz targets (afl)	2m 45s
public_private_dependencies	27s
cargo-semver-checks	29s
Fuzz targets (cargo-fuzz)	1m 7s
build_benchmarks	55s
	40m 19s

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