fix: hide simulation button pill value if no value loaded

[digiwand]

Description

In case no value was loaded in a permit simulation, then we should not display an empty value ButtonPill component.

Related issues

Fixes: #13662

Manual testing steps

e.g.

1. Go to https://develop.d3bkcslj57l47p.amplifyapp.com/
2. Trigger DAI
   We are also fixing this particular issue here: [Bug]: Missing "Unlimited" as value for DAI permit #13336. Adding this PR to be more robust and prevent other outlying cases

Screenshots/Recordings

Before

After

Pre-merge author checklist

• I’ve followed MetaMask Contributor Docs and MetaMask Mobile Coding Standards.
• I've completed the PR template to the best of my ability
• I’ve included tests if applicable
• I’ve documented my code using JSDoc format if applicable
• I’ve applied the right labels on the PR (see labeling guidelines). Not required for external contributors.

Pre-merge reviewer checklist

• I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• I confirm that this PR addresses all acceptance criteria described in the ticket it closes and includes the necessary testing evidence such as recordings and or screenshots.

[github-actions]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

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