[lib] Remove KeyserverInfoPartial type

Summary:
Following the Flow upgrade, I'm looking at replacing all usages of `$Shape` in our codebase. Context [here](https://medium.com/flow-type/announcing-partial-required-flow-utility-types-catch-annotations-3a32f0bf2a20).

When I swapped the `$Shape` in `KeyserverInfoPartial` into a `Partial`, it revealed a type error. The issue is that the `urlPrefix` and `connectionStatus` we pass to `createBoundServerCallsSelector` are nullable, but that function requires them to be set.

I investigated further and found that we don't actually use `KeyserverInfoPartial` in any case where its "partialness" is necessary... it appears we just get the `KeyserverInfos` from the Redux store and pass them in. As such, I deleted the type and replaced usages with `KeyserverInfos`.

Depends on D10082

Test Plan: Flow

Reviewers: inka, michal

Reviewed By: inka

Subscribers: ginsu, tomek

Differential Revision: https://phab.comm.dev/D10083

lib/utils/keyserver-call.js

@@ -72,11 +72,14 @@ type CreateBoundServerCallsSelectorType = (
   keyserverID: string,
 ) => BindServerCallsParams => CallServerEndpoint;
 const createBoundServerCallsSelector: CreateBoundServerCallsSelectorType =
-  (_memoize(baseCreateBoundServerCallsSelector): any);
+  _memoize(baseCreateBoundServerCallsSelector);
 
-export type KeyserverInfoPartial = $Shape<KeyserverInfo>;
+type KeyserverInfoPartial = $ReadOnly<{
+  ...Partial<KeyserverInfo>,
+  +urlPrefix: $PropertyType<KeyserverInfo, 'urlPrefix'>,
+}>;
 
-export type BindKeyserverCallParams = {
+type BindKeyserverCallParams = {
   +dispatch: Dispatch,
   +currentUserInfo: ?CurrentUserInfo,
   +keyserverInfos: { +[keyserverID: string]: KeyserverInfoPartial },
@@ -94,7 +97,7 @@ const bindCallKeyserverEndpointSelector: BindKeyserverCallParams => <
   (
     dispatch: Dispatch,
     currentUserInfo: ?CurrentUserInfo,
-    keyserverInfos: { +[keyserverID: string]: KeyserverInfo },
+    keyserverInfos: { +[keyserverID: string]: KeyserverInfoPartial },
   ) => {
     return _memoize(
       <Args: mixed, Return>(
@@ -122,7 +125,7 @@ const bindCallKeyserverEndpointSelector: BindKeyserverCallParams => <
               cookie,
               urlPrefix,
               sessionID,
-              connectionStatus: connection?.status,
+              connectionStatus: connection?.status ?? 'disconnected',
               lastCommunicatedPlatformDetails,
               keyserverID,
             });