[BUG][opensearch-dashboards] opensearch_security.auth.type not a valid key

[rdvansloten]

Describe the bug
When Attempting to leverage the security plugin, Dashboards pods crash and tell me:

{"type":"log","@timestamp":"2024-07-16T09:32:18Z","tags":["fatal","root"],"pid":1,"message":"InvalidConfigurationError: Unknown configuration key(s): \"​opensearch_security.auth.type\". Check for spelling errors and ensure that expected plugins are installed.\n    at ensureValidConfiguration (/usr/share/opensearch-dashboards/src/core/server/legacy/config/ensure_valid_configuration.js:50:11)\n    at Server.setup (/usr/share/opensearch-dashboards/src/core/server/server.js:156:5)\n    at Root.setup (/usr/share/opensearch-dashboards/src/core/server/root/index.js:60:14)\n    at bootstrap (/usr/share/opensearch-dashboards/src/core/server/bootstrap.js:113:5)\n    at Command.<anonymous> (/usr/share/opensearch-dashboards/src/cli/serve/serve.js:192:5) {\n  code: 'InvalidConfig',\n  processExitCode: 64,\n  cause: undefined\n}"}

To Reproduce
Steps to reproduce the behavior:

1. Go to your values.yaml
2. Go to the docs to get the args:
3. https://opensearch.org/docs/latest/security/configuration/multi-auth/#enabling-multiple-authentication-options
4. https://opensearch.org/docs/latest/security/authentication-backends/saml/#opensearch-dashboards-configuration
5. Add this in:

config:
  opensearch_dashboards.yml: |
    opensearch.hosts: [https://localhost:9200]
    opensearch.ssl.verificationMode: none
    opensearch.username: kibanaserver
    opensearch.password: kibanaserver
    opensearch.requestHeadersAllowlist: ["securitytenant","Authorization"]
    opensearch_security.multitenancy.enabled: true
    opensearch_security.multitenancy.tenants.preferred: ["Private", "Global"]
    opensearch_security.readonly_mode.roles: [kibana_read_only]

    # Use this setting if you are running opensearch-dashboards without https
    opensearch_security.cookie.secure: false
    server.host: '0.0.0.0'
    ​opensearch_security.auth.type: ["basicauth","saml"]
    opensearch_security.auth.multiple_auth_enabled: true

It does accept opensearch_security.auth.multiple_auth_enabled: true when I comment ​opensearch_security.auth.type: out. and boot up "correctly."

Expected behavior
I expected to be able to config SAML.

Chart Name
opensearch-dashboards, latest

Screenshots
If applicable, add screenshots to help explain your problem.

Host/Environment (please complete the following information):

• Helm Version: 3.15.2
• Kubernetes Version: 1.28.9

Additional context
Opensearch Helm values.yaml config:

securityConfig:
  enabled: true
  path: "/usr/share/opensearch/config/opensearch-security"
  config:
    dynamic:
      authc:
        saml_auth_domain:
          http_enabled: true
          transport_enabled: false
          order: 1
          http_authenticator:
            type: saml
            challenge: true
            config:
              idp:
                metadata_url: https://login.microsoftonline.com/REDACTED
    #SAML's metadata url, provided by your IdP
                Entity_id: https://sts.windows.net/REDACTED/
    #SAML's IdP entity ID, provided by your IdP
              sp:
                entity_id: opensearch-ad-sso
              kibana_url: REDACTED/_dashboards
              roles_key: Roles
              exchange_key: "REDACTED"
          authentication_backend:
            type: noop
        basic_internal_auth_domain:
          description: "Authenticate via HTTP Basic against internal users database"
          http_enabled: true
          transport_enabled: true
          order: 0
          http_authenticator:
            type: basic
            challenge: false
          authentication_backend:
            type: intern

Opensearch plugin list:

[opensearch@opensearch-cluster-master-0 ~]$ bin/opensearch-plugin list
opensearch-alerting
opensearch-anomaly-detection
opensearch-asynchronous-search
opensearch-cross-cluster-replication
opensearch-custom-codecs
opensearch-flow-framework
opensearch-geospatial
opensearch-index-management
opensearch-job-scheduler
opensearch-knn
opensearch-ml
opensearch-neural-search
opensearch-notifications
opensearch-notifications-core
opensearch-observability
opensearch-performance-analyzer
opensearch-reports-scheduler
opensearch-security
opensearch-security-analytics
opensearch-skills
opensearch-sql

[Divyaasm]

[Triage] Transfer to OpenSearch-Dashboards repo