Pull request: home: show version in install api

Closes #4026.

Squashed commit of the following:

commit bcd1315a10e819daee3aee323427d90a27860b4a
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Tue Jan 18 14:57:49 2022 +0300

    openapi: fix example

commit b56e27c5ac1fc7c3f595057d77607479d72ec50a
Author: Ildar Kamalov <ik@adguard.com>
Date:   Tue Jan 18 14:55:51 2022 +0300

    client: show version on install page

commit 95dfbfaa1235deef7b55e51457d11c677f6ef6b5
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Tue Jan 18 14:29:08 2022 +0300

    home: show version in install api

client/src/reducers/install.js

@@ -12,13 +12,19 @@ const install = handleActions({
     [actions.getDefaultAddressesRequest]: (state) => ({ ...state, processingDefault: true }),
     [actions.getDefaultAddressesFailure]: (state) => ({ ...state, processingDefault: false }),
     [actions.getDefaultAddressesSuccess]: (state, { payload }) => {
-        const { interfaces } = payload;
+        const { interfaces, version } = payload;
         const web = { ...state.web, port: payload.web_port };
         const dns = { ...state.dns, port: payload.dns_port };
 
         const newState = {
-            ...state, web, dns, interfaces, processingDefault: false,
+            ...state,
+            web,
+            dns,
+            interfaces,
+            processingDefault: false,
+            dnsVersion: version,
         };
+
         return newState;
     },
 
@@ -64,6 +70,7 @@ const install = handleActions({
         error: '',
     },
     interfaces: {},
+    dnsVersion: '',
 });
 
 export default combineReducers({