style: Adjust gap between pendings txs on dashboard widget

[usame-algan]

What it solves

Part of #3693

The space between pending transactions in the dashboard widget was stretched if there were less than 4 transactions.

How this PR fixes it

Instead of stretching the space, there is a fixed gap between each transaction. The gap is also slightly increased so that the space is filled when there are 4 transactions displayed.

How to test it

1. Open the safe app
2. Navigate to the dashboard
3. With less than 4 transactions, observe whitespace at the bottom of the widget
4. With 4 transactions, observe the pending tx widget has the same height as the featured apps widget

Screenshots

[github-actions]

CLA Assistant Lite All Contributors have signed the CLA.

[iamacook]

👍

[github-actions]

ESLint Summary View Full Report

Annotations are provided inline on the Files Changed tab. You can also see all annotations that were generated on the annotations page.

Type	Occurrences	Fixable
Errors	0	0
Warnings	0	0
Ignored	0	N/A

• Result: ✅ success
• Annotations: 0 total

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^{Report generated by eslint-plus-action}

[github-actions]

Deployment links

🟠 Rinkeby	⚪ Mainnet	🟣 Polygon	🟡 BSC	⚫ Arbitrum	🟢 Gnosis Chain

[coveralls]

Pull Request Test Coverage Report for Build 2239763962

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 35.33%

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Totals
Change from base Build 2233611204:	0.0%
Covered Lines:	3595
Relevant Lines:	9236

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💛 - Coveralls

[francovenica]

Weird, pretty sure it wasn't broken like that when we released it.

Looks good to me. The tx are listed from top to bottom with the same distance between the tx.

2 comparison snapshots from this PR and dev to see the difference:
This PR:

Dev: