Remove parse_conan_metadata_on_upload flag

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What does this MR do and why?

Remove parse_conan_metadata_on_upload flag that was introduced in !178728 (merged) and used to rollout the feature in #523693 (closed).

Changelog: removed

References

• #523693 (closed)
• !178728 (merged)

/cc @oceane_scania

Related to #523693 (closed)