fix: only allow one signal client instance at once

Signed-off-by: Heikki Hellgren <heikki.hellgren@op.fi>

plugins/signals/src/plugin.ts

@@ -22,6 +22,8 @@ import {
 import { signalApiRef } from '@backstage/plugin-signals-react';
 import { SignalClient } from './api/SignalClient';
 
+let clientInstance: SignalClient | undefined = undefined;
+
 /** @public */
 export const signalsPlugin = createPlugin({
   id: 'signals',
@@ -32,11 +34,15 @@ export const signalsPlugin = createPlugin({
         identity: identityApiRef,
         discoveryApi: discoveryApiRef,
       },
-      factory: ({ identity, discoveryApi }) =>
-        SignalClient.create({
-          identity,
-          discoveryApi,
-        }),
+      factory: ({ identity, discoveryApi }) => {
+        if (!clientInstance) {
+          clientInstance = SignalClient.create({
+            identity,
+            discoveryApi,
+          });
+        }
+        return clientInstance;
+      },
     }),
   ],
 });