feat(whale-api): whitelist getGovProposal, listGovProposals and listG…

…ovProposalVotes (#1922)

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#### What this PR does / why we need it:
Whitelist getGovProposal, listGovProposals and listGovProposalVotes RPC.
#### Which issue(s) does this PR fixes?:
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Usage: `Fixes #<issue number>`, or `Fixes (paste link of issue)`.
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Fixes #

#### Additional comments?:

apps/whale-api/src/module.api/rpc.controller.ts

@@ -39,7 +39,10 @@ export class MethodWhitelist implements PipeTransform {
     'getfutureswapblock',
     'getpendingfutureswaps',
     'sendrawtransaction',
-    'getrawtransaction'
+    'getrawtransaction',
+    'getgovproposal',
+    'listgovproposals',
+    'listgovproposalvotes'
   ]
 
   transform (value: string, metadata: ArgumentMetadata): string {