Rust

Merge pull request #1594 from coreos/dependabot/cargo/serde_json-1.0.138 #2849

Job	Run time
Lints, pinned toolchain (x86_64)	56s
Tests, stable toolchain (x86_64)	2m 11s
Tests, stable toolchain (s390x)	16m 41s
Docs	1m 14s
Tests, minimum supported toolchain (x86_64)	2m 33s
Lints, pinned toolchain (s390x)	7m 53s
Tests, minimum supported toolchain (s390x)	16m 46s
Tests, unstable toolchain (beta, x86_64)	2m 7s
Tests, unstable toolchain (nightly, x86_64)	2m 41s
	53m 2s

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