refactor(promexporter): use `otelRecorder` observer pattern (#2871) #32292

Job	Run time
Cancel Outdated Jobs	2s
Change Detection	40s
Get PR Metadata	0s
Go Generate (Solidity Only)	0s
Go Coverage (1.22.x, contrib/promexporter)	3m 11s
Lint (contrib/promexporter)	1m 55s
Go Generate (Module Changes)	0s
Remove Generate Label From Unused Jobs	0s
	5m 48s

Provide feedback