chore(env-manifest): update manifest file

Author: twilio-labs-ci

env-variables.manifest.json

@@ -83,48 +83,6 @@
         "contentKey": null
       }
     ],
-    "forward-message-sendgrid": [
-      {
-        "key": "SENDGRID_API_KEY",
-        "required": true,
-        "format": "secret",
-        "description": "Your SendGrid API key",
-        "link": "https://sendgrid.com/docs/ui/account-and-settings/api-keys/",
-        "default": null,
-        "configurable": true,
-        "contentKey": null
-      },
-      {
-        "key": "TO_EMAIL_ADDRESS",
-        "required": true,
-        "format": "email",
-        "description": "Messages sent to your Twilio number will be forwarded to this email address",
-        "link": null,
-        "default": null,
-        "configurable": true,
-        "contentKey": null
-      },
-      {
-        "key": "FROM_EMAIL_ADDRESS",
-        "required": true,
-        "format": "email",
-        "description": "The email address that SendGrid should send the email from",
-        "link": null,
-        "default": null,
-        "configurable": true,
-        "contentKey": null
-      },
-      {
-        "key": "TWILIO_SMS_WEBHOOK_URL",
-        "required": true,
-        "format": "text",
-        "description": "The path to the webhook",
-        "link": null,
-        "default": "/forward-message-sendgrid",
-        "configurable": false,
-        "contentKey": null
-      }
-    ],
     "voicemail": [
       {
         "key": "MY_PHONE_NUMBER",
@@ -197,48 +155,6 @@
         "contentKey": null
       }
     ],
-    "forward-message-sparkpost": [
-      {
-        "key": "SPARKPOST_API_KEY",
-        "required": true,
-        "format": "secret",
-        "description": "Your SparkPost API key",
-        "link": "https://www.sparkpost.com/docs/getting-started/create-api-keys/",
-        "default": null,
-        "configurable": true,
-        "contentKey": null
-      },
-      {
-        "key": "TO_EMAIL_ADDRESS",
-        "required": true,
-        "format": "email",
-        "description": "Messages sent to your Twilio number will be forwarded to this email address",
-        "link": null,
-        "default": null,
-        "configurable": true,
-        "contentKey": null
-      },
-      {
-        "key": "FROM_EMAIL_ADDRESS",
-        "required": true,
-        "format": "email",
-        "description": "The email address that SparkPost should send the email from",
-        "link": null,
-        "default": null,
-        "configurable": true,
-        "contentKey": null
-      },
-      {
-        "key": "TWILIO_SMS_WEBHOOK_URL",
-        "required": true,
-        "format": "text",
-        "description": "The path to the webhook",
-        "link": null,
-        "default": "/forward-message-sparkpost",
-        "configurable": false,
-        "contentKey": null
-      }
-    ],
     "airtable": [
       {
         "key": "AIRTABLE_API_KEY",