examples: Add a JWT authentication example (#5915)

examples/example-jwt-auth/settings.gradle

diff --git a/examples/example-jwt-auth/settings.gradle b/examples/example-jwt-auth/settings.gradle
new file mode 100644
index 0000000..59ef05d
--- /dev/null
+++ b/examples/example-jwt-auth/settings.gradle
@@ -0,0 +1,8 @@
+pluginManagement {
+    repositories {
+        maven { // The google mirror is less flaky than mavenCentral()
+            url "https://maven-central.storage-download.googleapis.com/repos/central/data/"
+        }
+        gradlePluginPortal()
+    }
+}