Allow use of "/" in Metrics Instrument Names

[aabmass]

• See recent spec change, Add "/" to valid characters for instrument names opentelemetry-specification#3684

And update the validation

opentelemetry-js/packages/sdk-metrics/src/InstrumentDescriptor.ts

Lines 89 to 94 in 4f28f90

	// ASCII string with a length no greater than 255 characters.
	// NB: the first character counted separately from the rest.
	const NAME_REGEXP = /^[a-z][a-z0-9_.-]{0,254}$/i;
	export function isValidName(name: string): boolean {
	return name.match(NAME_REGEXP) != null;
	}

Then update spec compliance matrix https://github.com/open-telemetry/opentelemetry-specification/blob/main/spec-compliance-matrix.md

[aabmass]

@pichlermarc can you assign to me?