[automation] Update EPR version to v1.22.0 (#1532)

Author: elasticmachine

internal/stack/resources.go

@@ -42,7 +42,7 @@ const (
 	PackageRegistryConfigFile = "package-registry.yml"
 
 	// PackageRegistryBaseImage is the base Docker image of the Elastic Package Registry.
-	PackageRegistryBaseImage = "docker.elastic.co/package-registry/package-registry:v1.21.0"
+	PackageRegistryBaseImage = "docker.elastic.co/package-registry/package-registry:v1.22.0"
 
 	// ElasticAgentEnvFile is the elastic agent environment variables file.
 	ElasticAgentEnvFile = "elastic-agent.env"