Hotfix: avoid page crash on loading :chainId/contractAddress (#3772)

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## PR-Codex overview
This PR updates a conditional check in the file `apps/dashboard/src/pages/[chain_id]/[...paths].tsx`.

### Detailed summary
- Updated conditional check for `configuredChain` to compare `getDashboardChainRpc` values for different chain IDs.

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apps/dashboard/src/pages/[chain_id]/[...paths].tsx

@@ -93,8 +93,9 @@ const ContractPage: ThirdwebNextPage = () => {
 
       const configuredChain = supportedChainsSlugRecord[chainSlug];
       if (
+        configuredChain &&
         getDashboardChainRpc(configuredChain.chainId) !==
-        getDashboardChainRpc(chain.chainId)
+          getDashboardChainRpc(chain.chainId)
       ) {
         setContractInfo({
           chainSlug,