"Apply suggestion to batch" button present on suggestions in MRs with one open and one applied suggestion
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### Summary
On fresh merge requests, the first suggestion you create only has the "Apply suggestion" button visible. Only after you create a second suggestion, the "Add suggestion to batch" button appears. That's a good approach, but when you have already applied a first suggestion, every new suggestion will have both buttons visible from beginning on.
### Example suggestion
https://gitlab.com/gitlab-com/www-gitlab-com/-/merge_requests/64369#note_424157143
### What is the current *bug* behavior?
It seems like our calculation of whether the "Add suggestion to batch" should appear does not differentiate whether suggestions are already applied or still open.
### What is the expected *correct* behavior?
We should only look at "How many open suggestions are there" when deciding whether the "Add suggestion to batch" should be displayed.
### Relevant logs and/or screenshots

issue