fix: update XigniteAdapter certFingerprint256 (#203)

## Description

This PR updates the Xignite certificate fingerprint. The previous fingerprint was outdated leading to an error in the client that stopped repors from the Xignite adapter. This update will replace the old fingerprint with the current one from the Xignite server, resolving the connection issue and restoring functionality.

## Other changes

- None

## Tested

- Verified updated fingerprint matches the current cert from https://globalcurrencies.xignite.com

## Related issues

- Fixes mento-protocol/mento-general#334

## Backwards compatibility

- N/A

src/exchange_adapters/xignite.ts

@@ -9,7 +9,7 @@ export class XigniteAdapter extends BaseExchangeAdapter implements ExchangeAdapt
   readonly _exchangeName: Exchange = Exchange.XIGNITE
   // Amazon RSA 2048 M02 - validity not after: 23/08/2030, 19:25:30 GMT-3
   readonly _certFingerprint256 =
-    'B0:F3:30:A3:1A:0C:50:98:7E:1C:3A:7B:B0:2C:2D:DA:68:29:91:D3:16:5B:51:7B:D4:4F:BA:4A:60:20:BD:94'
+    '68:96:35:0D:36:DC:54:53:36:5E:C9:FF:A1:76:56:C2:48:09:59:DE:FA:8F:E2:B7:1D:81:FF:B7:4B:FB:D6:7C'
 
   protected generatePairSymbol(): string {
     const base = XigniteAdapter.standardTokenSymbolMap.get(this.config.baseCurrency)