Add global label length limits #14

Job	Run time
Go tests on Windows	10m 21s
UI tests	2m 15s
Go tests	22m 40s
More Go tests	8m 11s
Mixins tests	3m 17s
Check generated parser	1m 5s
Build Prometheus for common architectures (1)	11m 17s
Go tests with previous Go version	12m 15s
Build Prometheus for common architectures (0)	11m 39s
Build Prometheus for common architectures (2)	11m 30s
fuzzing / Run Go Fuzz Tests (FuzzParseOpenMetric)	6m 35s
fuzzing / Run Go Fuzz Tests (FuzzParseExpr)	6m 44s
codeql / Analyze (javascript)	1m 29s
golangci-lint	3m 17s
fuzzing / Run Go Fuzz Tests (FuzzParseMetricText)	6m 39s
Compliance testing	8m 14s
fuzzing / Run Go Fuzz Tests (FuzzParseMetricSelector)	6m 35s
Build Prometheus for all architectures	0s
Report status of build Prometheus for all architectures	0s
Publish UI on npm Registry	1m 42s
fuzzing / Fuzzing	3s
Publish release artefacts	-1s
Publish main branch artifacts	-1s
	2h 15m 46s

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