opentelemetry-collector: Start order of extensions is not guaranteed?

Describe the bug Maybe I am misreading the situation, but this code iterates over map when starting extensions, so it cannot guarantee in which order they are started: https://github.com/open-telemetry/opentelemetry-collector/blob/e97ceca47f9eacf50688a5b2e40c0ad22261579b/service/extensions/extensions.go#L34

Even though the documentation implies that the order is define by the declaration order: https://github.com/open-telemetry/opentelemetry-collector/blob/e97ceca47f9eacf50688a5b2e40c0ad22261579b/docs/service-extensions.md?plain=1#L63-L66

I observed some spontaneous failures in my experiments with JaegerV2 which declares extensions with an order expectation: extensions: [jaeger_storage, jaeger_query] but the logs show differently:

2023-10-24T01:17:01.143Z	info	extensions/extensions.go:33	Starting extensions...
2023-10-24T01:17:01.143Z	info	extensions/extensions.go:36	Extension is starting...	{"kind": "extension", "name": "jaeger_query"}

Steps to reproduce It’s random behavior, hard to reproduce reliably.

What did you expect to see? Extensions should be starting in the order defined in the config.

What did you see instead? Seeing different order.

What version did you use? Version: v0.87.0

What config did you use? https://github.com/jaegertracing/jaeger/blob/28520b31471b36d9e949de4ffaa016c2640a3be7/cmd/jaeger-v2/internal/all-in-one.yaml#L1

Environment OS: MacOS, Linux Compiler(if manually compiled): go 1.20.x