fix(logs): add upgradeStrategy to collector config

[timojohlo]

Pull Request Details

Fixing the current issue in the opentelemetry-operator:
(check kubectl logs <operator-pod>)

OpenTelemetryCollector.opentelemetry.io \"logs\" is invalid: [spec.upgradeStrategy: Unsupported value: \"\": supported values: \"automatic\", \"none\", <nil>: Invalid value: \"null\": some validation rules were not checked because the object was invalid; correct the existing errors to complete validation].

hint: the docs currently state the field should be in PascalCase, but upgradeStrategy in camelCase is correct.