Fix typo in examples README: plural form examples #3868

Job	Run time
cargo-public-api-crates (axum)	2m 1s
cargo-public-api-crates (axum-core)	1m 22s
cargo-public-api-crates (axum-extra)	1m 41s
cargo-public-api-crates (axum-macros)	1m 23s
check	3m 42s
cargo-hack	8m 58s
check-docs	1m 13s
cargo-deny check (advisories)	33s
cargo-deny check (bans licenses sources)	32s
dependencies-are-sorted	1m 4s
Spell Check with Typos	7s
test-docs	5m 27s
test-nightly	4m 14s
test-versions (stable)	6m 29s
test-versions (beta)	8m 52s
test-msrv	10m 27s
armv5te-unknown-linux-musleabi	1m 45s
wasm32-unknown-unknown	42s
	1h 0m 32s

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