Remove four failure-joke greetings from homepage

What does this MR do and why?

Removes four greeting strings from the random greeting pool on the personal homepage (Your work > Home, the personal_homepage beta feature, enabled by default): "Rebasing: still not fun", "Git happens", "It works on my machine", and "It's not a bug, it's a feature".

Each page load shows one random greeting under the user's name. These four joke about software failure, which reads poorly as product copy. "It's not a bug, it's a feature" greeted a user in production and was flagged by Product Design leadership, who agreed all four should go.

39 general greetings remain in the pool, along with the time-of-day and day-of-week greeting pools, both untouched. locale/gitlab.pot is regenerated to match via tooling/bin/gettext_extractor.

References

• The merge request that introduced the greeting pool
• Slack discussion about removing the four greetings (internal)

Screenshots or screen recordings

Not applicable: the homepage renders one random greeting from the pool per page load, so a screenshot pair cannot demonstrate a change to the pool's contents. The diff and the passing specs are the evidence.

How to set up and validate locally

1. Sign in to a local GDK instance.
2. Open Your work > Home (the root path /).
3. Reload the page several times and confirm no greeting is one of the four removed strings.
4. Run yarn jest spec/frontend/homepage and confirm the suites pass; they read the live pool rather than hard-coding entries.

MR acceptance checklist

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