[1.14][identitygc] Bugfix: Pass shared EnableMetrics into GC struct

[jaredledvina]

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This is a 1.14 specific bug as on 1.15 and above there is #28166. 1.14 shipped with #22892 and it appears this got missed.

Currently when you run the operator with --enable-metrics that arg gets plumbed into SharedCfg but we never passed it into the GC struct. As a result metrics like https://github.com/cilium/cilium/blob/v1.14/operator/identitygc/kvstore_gc.go#L73-L79 aren't getting emitted on 1.14 as they are checking against GC not the SharedCfg. This changes ensures that we pass through the p.SharedCfg.EnableMetrics parameter to allow the conditional logic to work as expected.

I've tested this on a local 1.14 cluster and configured that with this change the metrics (i.e. cilium_operator_identity_gc_entries and cilium_operator_identity_gc_runs_ are once again emitted during identity GC.

Fix: Ensure enabling metrics turns on identity GC metrics

[hemanthmalla]

/test-backport-1.14

[pippolo84]

Nice catch, thanks! 🚀