[tsp-client] Update Node.js version for Ubuntu in CI workflow (#15937)

Author: mikeharder

.github/workflows/tsp-client-tests.yml

@@ -18,7 +18,7 @@ jobs:
       matrix:
         include:
           - os: ubuntu-latest
-            node-version: 20
+            node-version: 22
           - os: windows-latest
             node-version: 24