add security notice to github issue template

.github/ISSUE_TEMPLATE/bug_report.md

@@ -11,10 +11,15 @@ about: Create a report to help us improve
 
 **Helm Version:**
 
+
 **`helm get release` output**
 
 e.g. `helm get elasticsearch` (replace `elasticsearch` with the name of your helm release)
 
+*Be careful to obfuscate every secrets (credentials, token, public IP, ...) that could be visible in the output before copy-pasting.*
+
+*If you find some secrets in plain text in `helm get release` output you should use [Kubernetes Secrets](https://kubernetes.io/docs/concepts/configuration/secret/) to managed them is a secure way (see [Security Example](https://github.com/elastic/helm-charts/blob/master/elasticsearch/examples/security/security.yml#L23-L38)).*
+
 ```
 ```
 
@@ -30,4 +35,9 @@ e.g. `helm get elasticsearch` (replace `elasticsearch` with the name of your hel
 
 **Provide logs and/or server output (if relevant):**
 
+*Be careful to obfuscate every secrets (credentials, token, public IP, ...) that could be visible in the output before copy-pasting*
+
+```
+```
+
 **Any additional context:**