fix(all): [LW-8912] fix missing pending txs in activity & stuck infinite scroll on bigger resolutions

[refi93]

Checklist

• JIRA - LW-8912
• Proper tests implemented
• Screenshots added.

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Proposed solution

This PR fixes two independent bugs:

1. pending txs were incorrectly placed at the bottom of the activity list, resulted in their perceived "disappearance" from activity
2. while fixing bug 1 I noticed that the activity list remained "stuck" at loading on my screen which appears to be a result of a long-standing bug in the infinite scroll library (Not calling next function on long screens ankeetmaini/react-infinite-scroll-component#380) . A proper fix would probably involve patching the infinite scroll lib or replacing it with a completely different lib. For now I at least documented the bug with a comment and made a workaround to load enough elements to overflow the screen.

Testing

1. test fix for bug 1 try making a delegation, check that it appears at the top of the "Activity" tab while pending
2. for bug 2, check that upon initially opening the tab, the activities don't remain stuck in loading state

Screenshots

bug 2: Activity -> stuck loading, especially on full screen, fixed in this PR:

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Allure report

allure-report-publisher generated test report!

smokeTests: ❌ test report for b4ec4522

	passed	failed	skipped	flaky	total	result
Total	28	3	0	0	31	❌