feat: add startupProbe in collector pods

[lindeskar]

Description

Add startupProbe in opentelemetry-collector Pods.

It's basically a copy-paste of stuff from livenessProbe.

Fixes: #1152

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Background

We were hit by the same issue as #1152; long startup times due to compaction - leading to OTelCol Pods being killed before compaction was completed - leading to another round of the same.

Adding a startupProbe with a higher failureThreshold should be a nice fix.

Sometimes, you have to deal with applications that require additional startup time on their first initialization. In such cases, it can be tricky to set up liveness probe parameters without compromising the fast response to deadlocks that motivated such a probe. The solution is to set up a startup probe with the same command, HTTP or TCP check, with a failureThreshold * periodSeconds long enough to cover the worst case startup time.
From: https://kubernetes.io/docs/tasks/configure-pod-container/configure-liveness-readiness-startup-probes/#define-startup-probes