[stable/datadog] Fixes "merging map" warning messages with Helm 2 (#22436)

* Fix warning messages with Helm 2.x

Fixes warning messages like the below examples when using Helm 2.

```
Warning: Merging destination map for chart 'datadog'. The destination item 'confd' is a table and ignoring the source 'confd' as it has a non-table value of: <nil>
Warning: Merging destination map for chart 'datadog'. The destination item 'resources' is a table and ignoring the source 'resources' as it has a non-table value of: <nil>
```
Fixes #22428

Signed-off-by: Aditya Sundaramurthy <aditya.sundaramurthy@gmail.com>

* Bump chart version

Signed-off-by: Aditya Sundaramurthy <aditya.sundaramurthy@gmail.com>

* Updated changelog

Signed-off-by: Aditya Sundaramurthy <aditya.sundaramurthy@gmail.com>

* Bump chart version

Signed-off-by: Aditya Sundaramurthy <aditya.sundaramurthy@gmail.com>

stable/datadog/CHANGELOG.md

@@ -1,5 +1,9 @@
 # Datadog changelog
 
+## 2.3.4
+
+* Fix default values in `values.yaml` to prevent warnings with Helm 2.x
+
 ## 2.3.3
 
 * Allow pre-release versions as docker image tag

stable/datadog/Chart.yaml

@@ -1,6 +1,6 @@
 apiVersion: v1
 name: datadog
-version: 2.3.3
+version: 2.3.4
 appVersion: "7"
 description: Datadog Agent
 keywords:

stable/datadog/values.yaml

@@ -250,7 +250,7 @@ datadog:
   ## ref: https://github.com/DataDog/datadog-agent/tree/master/Dockerfiles/agent#optional-volumes
   ## ref: https://docs.datadoghq.com/agent/autodiscovery/
   #
-  confd:
+  confd: {}
   #   redisdb.yaml: |-
   #     init_config:
   #     instances:
@@ -431,7 +431,7 @@ clusterAgent:
   ## Each key will become a file in /conf.d
   ## ref: https://docs.datadoghq.com/agent/autodiscovery/
   #
-  confd:
+  confd: {}
   #   mysql.yaml: |-
   #     cluster_check: true
   #     instances:
@@ -987,7 +987,7 @@ kube-state-metrics:
   ## @param resources - object - optional
   ## Resource requests and limits for the kube-state-metrics container.
   #
-  resources:
+  resources: {}
   #   requests:
   #     cpu: 200m
   #     memory: 256Mi