[18.0] component: allow ctx override at init

[simahawk]

Before this change, the only way to set something in the ctx is to override the env property. This means that the code would be executed N times and a new env initialized N times.

The original env is preserved and in any case is available on work.env and collection.env.

[OCA-git-bot]

Hi @guewen, some modules you are maintaining are being modified, check this out!

[github-actions[bot]]

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