Add uri for people chains to the runtimes-matrix.json (#425)

Relates to: #186

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.github/workflows/runtimes-matrix.json

@@ -65,12 +65,14 @@
     "name": "people-kusama",
     "package": "people-kusama-runtime",
     "path": "system-parachains/people/people-kusama",
+    "uri": "wss://kusama-people-rpc.polkadot.io:443",
     "is_relay": false
   },
   {
     "name": "people-polkadot",
     "package": "people-polkadot-runtime",
     "path": "system-parachains/people/people-polkadot",
+    "uri": "wss://polkadot-people-rpc.polkadot.io:443",
     "is_relay": false
   },
   {