Fix Gitlab/JsonSafeParse: lib/gitlab/manifest_import/metadata.rb
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Fix Gitlab/JsonSafeParse violations in this file by replacing `Gitlab::Json.parse` with `Gitlab::Json.safe_parse`.
Related MR: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/215073
## Implementation Plan
A contributor needs to:
1. Replace `Gitlab::Json.parse` with `Gitlab::Json.safe_parse` in this file.
2. Verify with the MR reviewer that the new size and depth limits imposed by `safe_parse` do not break any existing functionalities. The `safe_parse` method includes built-in protections against:
- Excessively large JSON payloads
- Deeply nested JSON structures
Ensure that legitimate use cases in this file are not affected by these limits.
## References
To help you fix those violations, see the following guidance: https://gitlab.com/gitlab-org/gitlab/-/blob/18d80bbc5468cd2f987c5ea6abcf27709e40994a/.rubocop_todo/gitlab/json_safe_parse.yml
It is also recommended to read the following documentation on JsonParse:
- https://docs.gitlab.com/development/secure_coding_guidelines/#when-to-use-gitlabjsonparse
issue