feat(kube-stack): add command field support to collector template (open-telemetry#2096)

* feat(kube-stack): add command field support to collector template

The OpenTelemetryCollector CRD supports a `command` field, but the
chart's collector template does not render it. This adds support for
overriding the collector's entrypoint command through values.yaml,
following the same pattern as other optional fields like `args`,
`lifecycle`, etc.

Use case: users deploying BYO collector configs with init containers
that need to source environment files or wrap the collector binary
before starting.

* chore(kube-stack): bump chart version to 0.14.6

---------

Co-authored-by: Tyler Helmuth <12352919+TylerHelmuth@users.noreply.github.com>

Author: dpacheconr

charts/opentelemetry-kube-stack/Chart.yaml

@@ -1,6 +1,6 @@
 apiVersion: v2
 name: opentelemetry-kube-stack
-version: 0.14.5
+version: 0.14.6
 description: |
   OpenTelemetry Quickstart chart for Kubernetes.
   Installs an operator and collector for an easy way to get started with Kubernetes observability.

charts/opentelemetry-kube-stack/templates/collector.yaml

@@ -58,6 +58,10 @@ spec:
   nodeSelector:
   {{- toYaml . | nindent 4}}
   {{- end }}
+  {{- with $collector.command }}
+  command:
+  {{- toYaml . | nindent 4}}
+  {{- end }}
   {{- with $collector.args }}
   args:
   {{- toYaml . | nindent 4}}

charts/opentelemetry-kube-stack/values.yaml

@@ -176,6 +176,14 @@ defaultCRConfig:
   nodeSelector: {}
   #   nodeType: worker
 
+  # Command to override the collector's entrypoint
+  command: []
+  #   - /bin/sh
+  #   - -c
+  #   - |
+  #     . /node-env/env.sh
+  #     exec /otelcol-contrib --config=/conf/collector.yaml
+
   # Arguments for the collector
   args: {}
   #   arg1: value1