fix: Terrain cache local handling

[dalkia]

What does this PR change?

Corrected the way we store and delete the local cache, since the new version was prone to failure when the checksum was not the one that was stored

How to test the changes?

1. Delete all local terrain files
2. Enter the client and see the terrain. Explore the borders as well
3. Reset the client and repeat step 2. You are looking to the cached terrain now, everything should be the same.
4. Get out and delete only the terrain_cache_dictionaries folder
5. Repeat step 2
6. Get out and delete the terrain cache file
7. Repeat step 2
8. Repeat one last time step 2 to see once again the cached terrain

Our Code Review Standards

https://github.com/decentraland/unity-renderer/blob/master/docs/code-review-standards.md

[github-actions]

Windows and Mac build successfull in Unity Cloud! You can find a link to the downloadable artifact below.

Name	Link
Commit	70949e5
Logs	https://github.com/decentraland/unity-explorer/actions/runs/11075306576
Download Windows	https://github.com/decentraland/unity-explorer/suites/28944240873/artifacts/1988838340
Download Mac	https://github.com/decentraland/unity-explorer/suites/28944240873/artifacts/1988822245
Built on	2024-09-27T18:26:04Z

[anicalbano]

🟢 Reviewed by QA and working as expected!
This PR also include regressions for:

• Backpack and wearables
• Emotes
• Teleport
• Map and navigation
• Avatar locomotion
• Switching in between scenes with auto-dance and music
• Badges and My Profile

27.09.2024_15.38.16_REC.mp4