Bump codecov/codecov-action from 4 to 5 #1640

Job	Run time
Validate external types appearing in public API	1m 33s
Build rustls-cert-gen as a standalone package	32s
build (macOS-latest, stable)	4m 44s
build-windows	13m 32s
build (ubuntu-latest, stable)	5m 41s
build (ubuntu-latest, beta)	5m 58s
Measure coverage	5m 47s
build (ubuntu-latest, nightly)	5m 43s
Format & clippy	5m 45s
build (ubuntu-latest, stable 7 months ago)	5m 51s
Documentation (stable)	57s
Documentation (nightly)	1m 5s
Check semver compatibility	58s
	58m 6s

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