Validate only container component should have gl/inject-editor attribute

MR: Pending

Description

Currently, we support 2 types of components in a devfile - container and volumes. The gl/inject-editor attribute is used to identify which container component should be injected with the editor. However, when we make this check in our code, we do not check whether it is a container component; we only check for the presence of this attribute in any of the components. Thus, there is a possibility that someone could define the attribute in a volume component which would break this - https://gitlab.com/gitlab-org/gitlab/-/blob/5848f31b815919f481ca1a9e1c6b91a694608f98/ee/lib/remote_development/workspaces/create/post_flatten_devfile_validator.rb#L60

Acceptance Criteria

• When check for the existing of gl/inject-editor attribute in the devfile, only check for container components.

Technical Requirements

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Design Requirements

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Impact Assessment

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User Story

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