Loki chart fails to render proper YAML when add more than one extra manifest

[ngclinflows]

Describe the bug
Loki chart fails to render proper YAML when add more than one extra manifest, since --- YAML files separator is stuck to last character of preceding YAML files due to template whitespace chomping.

To Reproduce
Add at least 2 extra objects in values:

extraObjects:
  # Grafana datasource provisioning
  - apiVersion: v1
    kind: ConfigMap
    metadata:
      name: loki-datasource
      labels:
        grafana_datasource: "1"
    data:
      loki-datasource.yaml: "..."
  # Custom Alerting Rules
  - apiVersion: v1
    kind: ConfigMap
    metadata:
      name: loki-alerting-rules
    data:
      loki-alerting-rules.yaml: "..."

Leads to render something like:

apiVersion: v1
kind: ConfigMap
metadata:
  name: loki-datasource
  labels:
    grafana_datasource: "1"
data:
  loki-datasource.yaml: "..."---      # <--- missing new line before `---` separator
apiVersion: v1
kind: ConfigMap
metadata:
  name: loki-alerting-rules
data:
  loki-alerting-rules.yaml: "..."

Expected behavior
Renders valid YAML

Environment:

• Infrastructure: Kubernetes
• Deployment tool: helm

Screenshots, Promtail config, or terminal output
N/A