removing fuel when not supported

[Viterbo]

Fixes #134

Description

The fuel service is working as expected in the chains that are supported but are introducing problems in the not supported ones. This PR fixes the problem.

Test scenarios

• Login to testnet
• open the browser inspector and enter tab Network
• modify filters, select: Fetch/XHR
• try to sign any transaction (send tokens, stake or unstake)
• You should not see a POST request like this: https://telos.greymass.com/v1/resource_provider/request_transaction
• You should be able to perform the signing as regularly (without fuel)

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have cleaned up the code in the areas my change touches
• My changes generate no new warnings
• I have checked my code and corrected any misspellings
• I have removed any unnecessary console messages

[netlify]

✅ Deploy Preview for wallet-staging ready!

Name	Link
🔨 Latest commit	7a5e037
🔍 Latest deploy log	https://app.netlify.com/sites/wallet-staging/deploys/63edb8fde99b3f000870436b
😎 Deploy Preview	https://deploy-preview-135--wallet-staging.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site settings.