Get integration tests passing

Author: mgajda

server/src/test/java/io/envoyproxy/controlplane/server/EnvoyContainer.java

@@ -24,7 +24,7 @@ class EnvoyContainer extends GenericContainer<EnvoyContainer> {
   private final Supplier<Integer> controlPlanePortSupplier;
 
   EnvoyContainer(String config, Supplier<Integer> controlPlanePortSupplier) {
-    super("envoyproxy/envoy-alpine-dev:latest");
+    super("envoyproxy/envoy-alpine-dev:8fb3cb86082b17144a80402f5367ae65f06083bd");
 
     this.config = config;
     this.controlPlanePortSupplier = controlPlanePortSupplier;