fix: Don't trim trailing slashes from safe apps

[usame-algan]

What it solves

Resolves #4347

How this PR fixes it

• Doesn't remove the trailing slash anymore when fetching manifest.json and when adding custom safe apps

How to test it

1. Open safe apps from the list
2. Observe that they should still open
3. Add a custom safe app with a trailing slash
4. Observe that it should still open

Screenshots

Checklist

• I've tested the branch on mobile 📱
• I've documented how it affects the analytics (if at all) 📊
• I've written a unit/e2e test for it (if applicable) 🧑‍💻

[github-actions]

Branch preview

✅ Deploy successful!

Website:
https://safe_apps_trailing_slash--walletweb.review.5afe.dev/home?safe=eth:0xA77DE01e157f9f57C7c4A326eeE9C4874D0598b6

Storybook:
https://safe_apps_trailing_slash--walletweb.review.5afe.dev/storybook/

[github-actions]

📦 Next.js Bundle Analysis for safe-wallet-web

This analysis was generated by the Next.js Bundle Analysis action. 🤖

Six Pages Changed Size

The following pages changed size from the code in this PR compared to its base branch:

Page	Size (compressed)	First Load
/apps	48.39 KB (🟢 -11 B)	1009.56 KB
/apps/custom	40.02 KB (🟢 -11 B)	1001.19 KB
/apps/open	53.11 KB (-4 B)	1014.27 KB
/home	58.12 KB (-4 B)	1019.28 KB
/settings/safe-apps	23.92 KB (🟢 -4 B)	985.08 KB
/share/safe-app	9.72 KB (🟢 -6 B)	970.88 KB

Details

Only the gzipped size is provided here based on an expert tip.

First Load is the size of the global bundle plus the bundle for the individual page. If a user were to show up to your website and land on a given page, the first load size represents the amount of javascript that user would need to download. If next/link is used, subsequent page loads would only need to download that page's bundle (the number in the "Size" column), since the global bundle has already been downloaded.

Any third party scripts you have added directly to your app using the <script> tag are not accounted for in this analysis

Next to the size is how much the size has increased or decreased compared with the base branch of this PR. If this percentage has increased by 20% or more, there will be a red status indicator applied, indicating that special attention should be given to this.

[github-actions]

Coverage report

St.❔	Category	Percentage	Covered / Total
🟡	Statements	74.43% (-0% 🔻)	12882/17307
🔴	Branches	52.85%	3106/5877
🔴	Functions	58.62%	1894/3231
🟡	Lines	76.15% (-0% 🔻)	11706/15372

Show files with reduced coverage 🔻

St.❔	File	Statements	Branches	Functions	Lines
🔴	... / manifest.ts	40.48% (-1.38% 🔻)	4.17%	28.57%	45.95% (-1.42% 🔻)

Test suite run success

1504 tests passing in 204 suites.

Report generated by 🧪jest coverage report action from e77f5d2

[usame-algan]

We should decide what the expected behaviour is if a custom safe app without a trailing slash is added.

[francovenica]

LGTM

[katspaugh]

We keep adding this trimming and removing it. It fixes one thing and breaks another.
@usame-algan can you please find or write documentation on where the URL must be trimmed and where not?