fix(task-processor): the extraEnv where added in the wrong place

[blackjid]

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Changes

Fix bug introduced in thhis pr #187

The environment variables added for the task processor should go inside the container that runs the task processor rather in the deployment template spec.

The task processor was already including the api environment so it was not necessary to add merge both extraEnv

Also the extraEnv keys and values were added as yaml (key: value), instead of the expected object with the name and value keys.

How did you test this code?

I test it manually. With a values

api:
  extraEnv:
    ALLOW_REGISTRATION_WITHOUT_INVITE: false

taskProcessor:
  enabled: true
  extraEnv:
    foo: bar

The expected result in the api deployment, inside the flagsmith-task-processor container

env:
....
- name: ALLOW_REGISTRATION_WITHOUT_INVITE
  value: "false"
...

and in the task processor deployment, inside the flagsmith-task-processor container

env:
....
- name: ALLOW_REGISTRATION_WITHOUT_INVITE
  value: "false"
- name: foo
  value: bar
...

[zachaysan]

The changes look reasonable to me, but I lack experience with this repository so I've tagged @khvn26 for a review that would come with an approval stamp on this PR since he knows more about this repository than I do.

Thanks for contributing!