Update renovate config not to update to caffeine 3 (open-telemetry#2397)

Author: trask

.github/renovate.json5

@@ -81,6 +81,16 @@
       ],
       enabled: false,
     },
+    {
+      // caffeine 3+ requires Java 11+
+      matchPackageNames: [
+        'com.github.ben-manes.caffeine:caffeine',
+      ],
+      matchUpdateTypes: [
+        'major',
+      ],
+      enabled: false,
+    },
     {
       // junit-pioneer 2+ requires Java 11+
       matchPackageNames: [