chore(ci): update Datadog Agent version to 7.78.4 (#1672)

Author: dd-octo-sts[bot]

.datadog-agent-version

@@ -1 +1 @@
-7.78.3
+7.78.4

.gitlab-ci.yml

@@ -46,8 +46,8 @@ variables:
 
   # Converged Datadog Agent-specific variables, which control how we build the converged Datadog Agent image that we
   # publicly publish.
-  PUBLIC_DSD_VERSION: "7.78.3"
-  PUBLIC_DD_AGENT_VERSION: "7.78.3-jmx"
+  PUBLIC_DSD_VERSION: "7.78.4"
+  PUBLIC_DD_AGENT_VERSION: "7.78.4-jmx"
 
   # Base images to copy Agent Data Plane into, depending on whether the image is meant for our internal environment or
   # public registries.

docker/Dockerfile.datadog-agent

@@ -1,4 +1,4 @@
-ARG DD_AGENT_VERSION=7.78.3-jmx
+ARG DD_AGENT_VERSION=7.78.4-jmx
 ARG DD_AGENT_IMAGE=registry.datadoghq.com/agent:${DD_AGENT_VERSION}
 ARG ADP_IMAGE=saluki-images/agent-data-plane:testing-devel