guess_language: add flake.lock as json #3185

Job	Run time
Test with MIME database	4m 7s
Actionlint	59s
Test x86_64-unknown-linux-gnu	4m 5s
Rustfmt	1m 25s
Test x86_64-apple-darwin	5m 0s
Output Regression Test	4m 16s
Test x86_64-pc-windows-msvc	4m 31s
Check Linux Packaging	3m 45s
Test Linux (latest stable Rust)	2m 11s
Test aarch64-unknown-linux-gnu	5m 27s
Test aarch64-apple-darwin	3m 24s
Test x86_64-unknown-linux-musl	4m 35s
	43m 45s

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